Pistols desperately need a buff. All machineguns outdo them in every single way. Pistols should have a huge speed buff, along with a chance to wound (as in, slowly sap away health from the opponent). That might even things out.
This is the best FPS I have ever seen. The gameplay is fluid, it requires actual tactics to play, and everything is quite well balanced. However, sniper needs to become more ineffective at close range. All in all, 5/5.