Hi @f2p_2021 
Yeah, I’m wordy at times…my apologies!
And nothing at all provoking about your question(s); on the contrary, they’re intriguing and I’m just a person that couldn’t answer it…thus no bonus points for me, lol! 
Thank you for taking a moment to check us out and for sharing your thoughts. 
Yup! Shortly after my initial reply, we went from 29/30 back to full; nevertheless, I wish you success in your quest for the alliance you’re looking for 
Best wishes,
Kerrang
Move up. Hopefully there are a few more good options.
In my opinion invite only is for people you chatted with in ar directly and ivited them to join you. This does not mean there are people you didn’t directly invite join, it just gives more control of who you let in. I am a coleader of The Fantastic Core, and we stay full mainly because we have a fantastic group of people and do have a waiting list only in top ~500-1k. We fit all your criteria with being full the only exception. We don’t require line just prefer it so we can send titan war reminders because hey nobody is perfect and can forget to use flags from time to time. But when I say we are full and stay full, we haven’t had an opening for 2 to 3 months.
@Heim459 I understand the idea of being invite only if you have a waiting list of people wanting in. I’m a bit more surprised that an alliance like yours has a waiting list because on the first glance you don’t look anything special. Anyway, I can agree that it might be a good choice for your alliance.
We really aren’t other than everybody chooses to stay put because there’s no pressure to perform at a certain level other than use all flags in war and hit the titan when you log in. We are on 12/13* titans and use all flags every war with an occasional rl situation getting in the way of war. We are a merge of 2 alliances both having 12-13 each and so only had to fill 5 or 6 spots. A successful merger and we stay full with very little turnover. We must be doing SOMETHING RIGHT.
Ouch. More reason I suppose to check them out @f2p_2021.
Adding my 2c. My alliances were invite only, as we only wanted like minded people to join. The sort who would use all war flags and assist in taking down titans. There have been lots of experiences shared of unscrupulous players joining, only to leave shortly after, without using any flags, and putting undue pressure on others.
We avoided such situations by controlling who enters. The Line app & Discord have been invaluable. And also, reaching out to friends of friends who are known to be “good” people. Anywho, GL in your decision making.
Congratulations 
Successful mergers can be difficult to achieve.
My guess is they are similar to the alliance I’m a member of. In our case they never recruit and getting a spot takes a bit. It’s all totally worth it when you are surrounded by like minded peeps.
Quality over quantity.
@sft1965 I totally support the idea of having like-minded members in your alliance. My question is how being invite only actually helps it in practice? It does help if you want to remain a closed group of the same people and don’t want any new members. This might be a case for you and I can understand that. But I was a replying to a recruiting ad in my topic so they seem to want new members in.
The “Kick” button really helps keep quality over quantity for an usual alliance (i.e. outside let say top 150). @Heim459 Could you share your experience? in which scenario being invite only helped your alliance in practice?
It helps to keep out the riff raff. 
If you are an open alliance anybody can join, which is good if you are requesting merc help on titans. Otherwise invite only makes it so you request in and someone has to accept you into the alliance. It really isn’t that big of a difference, except there are trolls in the game that enter and leave flags for war on purpose and stuff like that. It helps keep trolls out. I think an invite only alliance is top 1k and they are legitimate alliances.
I’m sorry I caused some annoyance to you. We are open to new members but are selective… We have no onerous rules (100% flag use is expected if opted in to AW but life still happens sometimes) and it keeps things nice (for us anyway). I’d rather rely on mutual respect than the use of threats to keep peeps in line.
Best of luck.
@Heim459 @sft1965 My question remains the same: how being invite-only actually helps you achieve those goals in practice? Could you provide some realistic scenario? To the best of my knowledge it doesn’t help filtering any kind of bad players on their first entry. But of course I might be missing something and then I really would like to know so that I can mend my ways.
For example (obviously not realistic):
There are a some unreliable players in the game who can ruin your war by leaving. If you are open, you can be their next target. But because those players physically can’t press the “Request to Join” button we having an invite-only alliance are safe.
or
There are some drama kings/queens in the game who can ruin good mood in the game. If you are open, you can be their next target. But we, being invite-only, have a big warning in the chat when such a players tries to join so we do not accept such requests.
Seriously, there is a mass variety in players and sub lvl 40 are welcome if vouched for or have a ‘reputation’ and frankly I thinks ours punch above their weight.
However, I firmly believe a new member approval should require at least more than a ten minute chat. In our case it is also contains a “does anyone have an issue with this member joining?”
Invite only lets you be more selective about who you accept, as has been mentioned by other contributors here. It also lets you verify roster and troop depth before accepting someone, as well as speak with them to confirm they are going to fit in your alliance, while also giving whomever is applying the opportunity to see if the alliance they are requesting would even be a fit for them instead of just blinding joining. The scores and member levels you can see as an outsider are only a small part of what makes a successful alliance work.
We are a top 100 alliance when full, but have been hanging around 28/30 for a while now and are still killing every Titan and winning wars, so we don’t really have any issue with staying invite only and being selective to make sure the right teammates come in. We’ve also left the door open in the past and have had one or two members walk in that have stayed with us and worked out, but in general we’ve had to kick far more people walking in for either not communicating, not hitting titan, etc than we have kept and honestly that is just a pain after a certain period of time.
Another reason to keep the door closed is that all elders and above can accept/kick members, but only leads/coleads can open and shut the door. Typically alliances are structured to have more elders than coleads, so it is the path of least resistance.
@sft1965 What information do you use for new member approval? What additional information does being invite-only provide for you to make that decision?
An application, roster reveal (for me anyway) a long DM discussion about fundamental principles, both game play style and capacity and to a minor but important extent personal principles and the treatment of others. A forum member to vouch for you and you stand on your merits (or lack of) but own them is very useful. In some ways, iit’s an interview to join an extended friends group.
@AmphibiousChris As you can see in the very first post I understand being invite-only for the top 100. If you want to screen the roster as you might want for top 100, it makes sense. But there are maybe 150-200 alliances who regularly hit top 100. My question is about all the others.
As for talking beforehand I’m not sure how does it help especially given that people being smart a capable of lying. And as for this part
how does talk substitute for the real experience of actually trying to play together? Do you really believe that roster is everything and skills doesn’t matter at all in this game? Or do you have some way to measure skills by talk? And how does the person wanting in can measure your skills and attitude by talk?
This part I didn’t get at all. Could you please elaborate? How being open contradicts having only a few co-leaders?
The roster gets you in the door. A good alliance understands the minimum number of maxed heroes you need to be effective at the level you are applying for.
I don’t believe talk substitutes for skill, although a good portion of this game is RNG, but lets say for instance our war strategy requires you to use all your flags immediately as soon as you get them, or we require a 100k hit every Titan, or you need to churn through a certain number of player levels each month, or maintain a certain level of cups, etc, etc. Where in the open alliance description do you get this info?
I can’t tell if this is a troll attempt because you are arguing that every alliance should be open because no discussion is needed and there is no benefit to team building, yet you have a forum post meticulously selecting an alliance open for several weeks with extremely specific requirements. Either way, we’ve gotten off track here. Good luck to your new alliance.
@AmphibiousChris do you really have a unique war strategy? Or is the titan minimum requirement any unique? And finally do you suggest that somehow being invite-only makes it easier for the people joining it to find out all that information? That’s a really interesting logic 
If you are outside of top 100 (which is an explicitly stated premise for the whole argument) how do people even find out about you? They either see your ad somewhere (and this is surprise a very good place to put all that info) or you have some common friends so they have an easy way to find everything out. Obviously you put Line or Discord of your Leader/Co-Leader in the description so people can find out more details if they want.
Where did I ever said there team building is wrong or bad or something similar? What I said is that for most of the alliance I see no benefit to effective team building by being invite only. I asked a few people in this thread to provide some realistic scenario in which being invite-only-by-default somehow helps in team building for an alliance outside of the top 100 and so far I don’t see any. (If I somehow missed it, I’d be grateful if someone point me to the relevant message).
P.S.
If that is a real requirement of your alliance of some of the alliances you personally know, I’d be very interested in finding out the reason why. I can’t imagine a good reason myself. Being a higher level player of itself doesn’t seem to provide any advantage to the alliance. And I can’t imagine that in a high-level alliance people can level up often enough to make any significant difference in titan hits from those additional free hits by level up. But again I might be missing something and I’m very interested in finding how to play this game more efficiently.
P.P.S. As for the alliance search the quest goes on I’m a bit surprised and disappointed that apparently there are no more such alliances left in the game. I know from personal experience such alliances do not tend to last for years, I’ve seen at least 2 or 3 such alliances die. Still it was quite a good fun being a member while they were alive.