Excuse me, if I didnt read attentively, but this idea is works already some time, for example TTTLA + C88 like CoA. If i know, they havent problem swarmed another smaller factions. Next ones can be The eaceKeepers, The Panzers, GN13...
You guys, will have propably under one faction almost each smaller gangs, which havent a change to get some TC or PVP, its good for me and rightly for others and I support it.
But!
What will you do, if got for example twice more people, then enemies, which start take your city. Does it means, that you first time check number of enemies and then half of people which come to TS, Mumble, whatever to enjoy some fight, will not go to action? I think it wil be not work, its hard them say: "no, we got enough people go back to craft, just half of people here can go to TC".
I think that by the time, you will have the most people on the server and only you like one faction will do TC, so its a same case like TTTLA alliance.