getting the first/second level in KF is pretty easy. mostly making headshots with certain weapons.
You got unlucky with a couple of those attempts at multiplayer, for the most part the KF community are pretty friendly. Your class doesn't count for much, just gives bonuses to certain weapons/skill. example, I play sniper class but rarely take rifles. I mostly use all the pistols. I can empty those fuckers faster than anybody can empty an assault rifle, and point blank against one of the bigger bastards means a ton of DPS more. Near the end of rounds though, ive usually got the crossbow and only one pistol set.
[edit]
I said "better DPS" I meant "comparable." most of the pistols have a long reload time. also, the guys that say "why didnt you pick up my equipment," if im picking up their equipment, they aren't getting it back because I dont know how to drop it. they should be more worried that I did pick it up. they can pick it up themselves anyway at the start of the next round.