A few questions about RoguesFollow

One on one PvP breaks down to do you have surprise or not. Many rogue builds specialize in status lock and will generally rule 1 on 1 PvP, if you get the opening shot. They can be dodgy of you are starting out in a duel situation or they know you are coming.

In group play, you don't have the utility spells of other classes, you will be a puller/scout. You have one utiltiy ability that lets you take one human mob out of combat but you can only use it before combat has started. Mostly you will be about damage, damage, and damage (If you have a good tank you can try to juggle agro but this will not be your job in an instance with 2-6 mobs attacking your party.)

Rogues depending on build and weapons can front load damage, do DoTs, do steady damage or have huge finsing moves. It depends on how you want to build it. (Example I am a combat speced duel sword rogue I rely on Garotte and Ruptur to dot abilitys and my large damage swords to make my sinster strike dish huge numbers. I am more useful solo, becaues in a group I can't backstab and I tend to draw too much agro.)

You damage comes from both your weapons and abilities. Most of your abilites are weapons damage + x, or x% of weapons damage.