After playing this game for a while, I am determined that it is not the strength of my roster (way too many stronger than mine), nor is how competitively I rank amongst the raid arena / challenge events. It is actually the aesthetic aspect of this game, the base look functional enough, but aside from the Titan / Alliance Wars / Chat, nothing really bridges alliance members together.
Building on my previous idea regarding having an Alliance Titan Bestiary (which I still would like to see happen, despite not seemingly getting any traction)
I would like to suggest an alliance monument building project that each alliance tackle on its own. The monument just takes a significant (borderline absurd amount of iron, or if possible, ham or other raw materials to make it more realistic) that each alliance member can contribute from his / her own inventory to the alliance monument building whenever and however much desired. The purpose of this is for aesthetics foremost, but it shows the combined strength of an alliance when it comes to a group project. Sure, there might not be an actual purpose (in terms of rewarding resources, etc.), but it’s all about team building. If an alliance is inactive, the project stays unfinished, and if an alliance is wiped, the monument is of course gone, it is also an indicator of how active an alliance is.
The devs can also opt to make monument building a Mission in the Mission Log as well. Like finish 5 monuments (means you got to join an alliance to do that) and get a background (not game altering). An idea would be a Hall of Heroes that could “host” or “exhibit” the above mentioned Titan Bestiary.