For all of you looking at squad... while it's a future based effort, take a look at planetside 2, it's free (completely) and has... quite a bit of what you seem to be looking forward to in squad. The battles aren't just 50v50 though (more like 150v150, map size is more large island than decent sized town).
It has the whole "battles can vary bit" going on. It might end up being a massed foot zerg or one faction pulls armour which leads to yours rolling aircraft, enemy pulls AA, etc. There's a cash shop, yes, but the basic weapon loadout is decent/balanced and everything unlocks with experience (essentially). I never get why PS2 doesn't get a bit more love (maybe it's the learning curve, it's quite like counterstrike for learning the ropes).