You can use credits (earned by playing the game) to buy weapons before they are unlocked at their level (you can buy the archer rocket and use it before level 45) I suggest buying either the G2 or the Hemlock. The G2 is a single shot weapon that can 3 hit on the torso The Hemlock is a 3 round burst rifle. If you take advantage of the recoil you can one hit people with it As for titans I enjoy scorch with the thermite shield perk. I love charging at an enemy titan and quite literally melt them with the shield