AvA is an option that is just a good idea to have around. There's a number of people who want to play like Jimson stated, don't want allied vs allied/axis vs axis. Between that and the stuff they can fiddle with that the MA's can't, I think it'd be a really bad idea to get rid of it.
EW and MW I don't think are terribly useful, but then again, the LW provides me with what I want most of the time, and when it doesn't, EW and MW sure wouldn't either.
Wiley.