None of them if you are looking for multiplayer.

Far Cry's multiplayer is pretty dead or has a tiny player pool.

I think you'll probably find no games in SEA.

Might as well take the FC4 key and sell it. ACU is terrible as it might be buggy and The Crew is a shitty racing game. FC4 is the best game Ubisoft released this year but if you want multiplayer, i doubt any Ubisoft games can satisfied your demands.