My opinions on Multiplayer..
Don't make it arcady, but don't make it real life either.
Take away the whole, 50,000-M249-SAW-rounds-to-the-head-is-a-flesh-wound idea that Far Cry 2 had.
Give the maps smart designs and don't make them two inch squared boxes like Call of Duty. In a LOT of cases, that simply depletes teamplay, not promotes it.