I have actually spoken to separate devs and gms with regards to what they can and cannot do. The shrine bug was one good example, as shrines are coded in the engine, and not able to be altered by the quest design or a mod. Having actually spoken to devs with regards to this type of thing I KNOW that the chat aspect of the game is coded in the engine and not an easy thing to fix.
Would something like this affect me in one way or another... yes. The time spent working on the game engine would be immense, taking away from other aspects of the game which would affect my enjoyment of the game.
Besides... your guild leader could /tell OtherGuildLeader hey, we're forming a Reaver raid at around 8 tomorrow night, we've got 5 ready right now, see if you can get some more. And the problem would be solved.
My point is that there are some serious bugs/holes/exploits/things wrong with this game as is... and this "guild alliance" thing is fluff compared to adding new content and fixing the existing content. Especially considering you already have most of what you want... you just have to use it the way it was intended.