Weapon choice depends on playstyle and situation.
As LA your obvious advantage is mobility. Using you can flank, distract, ambush. You can reach high places like the antennas and towers which give good opportunity to survey your surroundings and make it easy to spot sunderers and other enemy movement.
Always try to get behind enemies you engage,
Try and stay above, going on rooftops, trees anything that lets you be above the action.