Man Killzone is so fun.
I'm buns at KZ. I need guidance, BADLY.
Im playing multiplayer @stopcappin
Depends on what class you want to run, but I can really only speak on Scout, as that is what I have been doing. Im pretty much maxed out, just completing abilities before I move on.
First of all, do not worry about your K/D ratio. Ever. At all. Its not important, it doesnt matter. Even in TDM. You can finish first in this game without even killing anyone (well, hard to do in TDM but possible). Just work on challenges and upgrading your gear.
First thing, get used to the speed of the game. Its slower than most FPS. Adjust your horizontal and vertical, as it will help a ton. (Options in match) I have mine both at 70% and it feels alot better than default.
Two, use your abilites at all times. Almost important as shooting your guns. I run Stun Drone and the sonar ability. Sonar lets you know where enemies are in close proximity. Stun obviously stuns enemies for a short period. I make sure I am always using them. They give you a ton of points. Stun droids knock out other droids, shields, and get you assists if someone kills your stunned enemy. Sonar or Echo I think its called lets your team know exactly where the enemy is. Again, points from assists. The more you use them the more they level up.
Sniping is alot more difficult in this game as head shots are harder to get. It took me a while to get used to it again.
One thing I highly recommend if you are new and you want to still contribute is the support class. Respawn points will WIN YOU GAMES. The maps are huge and I HATE when my team doesnt have at least one set up. Also ammo drops and healing droids can get you a ton of points.
Just mess around with it. It isnt as "pick up and play" as COD or BF, but I find it a great mix of the two. If you really stick with it, it isnt hard to get good at. TDM is good, but Warzone is the best with rotating game modes to always keep people moving and prevent the campers.
As I type this my game save was corrupted.
Still have all my MP stuff, but all my campaign progress was lost.