Regarding the game performance: the sound tweak is changing a line in your default.con file. See here: http://home.comcast.net/~loudspeakermusic/help.html I would also suggest (for the time being) ignoring the EAX support and setting sounds to use the Miles 2D setting.
I agree about the infantry - the game feels as BF42 should have done; that infantry are the prime assault method with vehicle support, not the other way around. I believe that the stars ingame represent the highest three scores. Once nice touch is that you get 1 point for neutralising an enemy flag and another 2 points for turning it to your team.