They are all good heroes. I use Belith all the time as my top healer and when I need a dispeller. My Brienne is 3/41 but her skill is 4/8 right now, I don’t use her much as I have Wu and Kiril but, I know she is favorite of many (@zephyr1). I really enjoy Melia she is usually my second yellow color stack after Bane for raids (I just can’t seem to get the handle of Wu on raids love him for titans obviously)
Just wondering what everyone else’s thoughts were.
I like all three of those too. Brienne is the one I like the most though. In combination with Gunnar or Kailani (or Wilbur or Aegir, if you’re lucky enough to have either of them), she can be a real monster. Fantastic against titans, in particular. Use her special and gunnar’s/kailani’s right before the titan fires its’ special, and you instantly have five heroes at +144% attack for five turns. (Unless it’s a green titan, that is.)
Go with whichever one you use the most often
All three are excellent heroes, but Brienne and Melia are far more likely to last in usage even as you get other heroes.
Belith is the best 3* healer, but any 4* healer will quickly take her place.
In contrast, Brienne and Melia both pack 5* skills into 3* bodies. They can be used even on big titans to great effect. Using Emblems to add to their survivability for longer-term usage is a reasonable investment.
And neither can be easily replaced in skill.
Between the two of them, Brienne is the more likely to get use for a long time to come, in my opinion. A buff to Crit Chance can make a sizable difference in damage output, but Brienne can turn even a team of non-hitters into a death squad.
Her attack buff is just massive, especially if paired with a spirit linker like Gunnar, Kailani, or Wilbur — who are all also natural choices for Titan and Quest survivability. That pairing can easily serve as the foundation of every one of your Titan teams, even on bigger titans, and on Quest/Event teams.
Because of that, I’d pick Brienne over Melia — prioritizing Titan and Quest/Event teams is the best way to increase your chances for ascension mats that you’ll ultimately need for 4* heroes. So that will best serve your long-term progress.
Thanks @zephyr1. Does your analysis take into account the fact that I have Wu? I’ve used Wu and Melia together on purple titan to devastating effect. I kinda felt like Wu made Brienne a bit redundant and mostly I would use her for War, Quests and Challenge events.
I have never tried Wu and Brienne together. With spirit link could be worth a go. Means firing off a ton of mana potions right from the get go…
Wu and Brienne stack.
Wu doesn’t make Brienne redundant, he makes her nuclear.
Try it, you’ll blow a hole through concrete walls.
You can keep doing that too…and could bring Brienne too while you’re at it. 
I’d only mana up your Spirit Linker, to help with survival. Leave the rest to board mana, or you’ll run out of mana pots in the long run.
That said, if you want to go crazy every now and then and see a super active board coming, if you mana up Brienne, Wu, and a Spirit Linker and get hit once before you make a big match or blow a Diamond, you’ll likely do more damage from that one move than most of your titan hits.
Just a random thought. When a hero dies their attack stat still factors into tile damage. I assume any buffs on the hero die with them and would no longer effect tile damage. Has this been confirmed? Otherwise you could just bring all buffers and let them die and just focus on tiles.
Yeah, when they die, whatever buffs (and debuffs, for that matter) were active on them before they died, go away.
That’s exactly the strategy against titans as long as one is alive…
Buff attack as high as possible, lower the titans attack and defense. Then go for the weak point and/or heavy tile combos as fast as possible. Hit all specials immediately and sort your specials from left to right to go even faster.
The hitting specials (even Liannas) itself are like throwing cotton balls when facing titans.
Event quest wise, both Brienne and Melia are great choices. Although Melia overall will see more use, because Holly heroes rock all those quests except Teltoc.
Melia is at her best in Corellia, she’s also useful in some levels of Avalon, Wonderland, and Grimforest.
Brienne is at her best in Avalon. Also good in some levels of Grimforest with blue minions.
Event quests aren’t everything of course, so if you don’t care about high scores, then I’d go with Brienne.
One thing to consider is that spending emblems on Melia over Brienne will increase her attack as well as her defense so she’ll do more damage when her special goes off. I know it’s not much but it might be enough to tip the scales for me.
I would like to compete on the rare levels for at least the next 6 months or so. Eventually I’ll take all my emblems off of 3* and move them to 4s and 5s but it’s going to take me a long time to get to that point. Right now I can’t even complete epic but I scored in the top 30K for the last challenge. I know it’s not much but it’s something to shoot for. I figure a lot of more advanced players won’t bother putting emblems on 3* so this could give me an advantage. My Valen is at +18 with Revive maxed. He’s like a mini 4*. I have had him come back many times during raids, quests and titan fights.
I asked this question recently myself to aim for the top 100 in the coming quest, being Teltoc: Teltoc Challenge Quest - Help building out my Rare Tier team. Some very helpful replies there, including longtime 3* hero expert Wharflord who I’ve seen in the leaderboards several times.
Me, the highest I’ve ever made it was Grimforest at 138th place, so close and yet so far from top 100. That was before I knew the info I know now.
The TL:DR was to go for monocolor teams and keep replaying until a good board + run happens to get the best scores, or go for two colors (3-2) for consistency. Tweak it as needed depending on the minions, and bomb the bosses with offensive items (after a good run).
I didn’t really get any replies on emblems, so I’m holding off on that myself, but if your best heroes are 3 stars then I think it’s fine if you use them.
EDIT: I should actually also add that the forge levels for allowed craftable battle items in all tiers:
Rare: forge level 10
Epic: forge level 14
Legendary: forge level 20