I have only been playing this game for just under a month, but a couple of things I reckon would improve this game are:
For Alliances:
the ability for clan leaders to nudge other players to notify them to either hit titans, attack in war or just send them a message because they arent contributing enough
would be great if clan members could donate food and iron to other clan members (maybe a max of not to much to effect the game too much)
also would be nice if the devs could close inactive Alliances after a certain amount of time. Because when you search for an alliance there is SO MANY inactive ones its not funny.
Builders: (I mentioned this in another topic)
-the ability to be able to upgrade a builder, so that anything you are crafting can become a little faster. Heroes, buildings and crafting. There are many ways to do this and im sure the devs could come up with a way so it doesnt hurt the game, but only help it and make it more enjoyable.
I reckon these would make the game better IMO and would love to know what others think (specially the Devs) cheers.