Advice for Burglar builds

I am looking for help for a friend that plays a Burglar mostly solo with some previous 3/6/12 man content mostly on T1. He would like to start doing T2 content and the raid either T1 or T2. They are fairly well geared with 4 slot level 100 armor and some 105 4 slot armor along with 2 slot FI jewelry and 3 slot level 100 crafted jewelry and BB Gold jewelry available. I am looking for advice on what line they would be most helpful to be in for a Raid/6/3 man (I am thinking yellow) and a good trait build suggestion. Also, what skills should they be focusing on to debuff the bosses / other mobs? Finally, are there set bonuses from armors/jewelry that are helpful and what stats should they be looking for? I would imagine they should be at mitigation caps and around 28k+ morale, is there another important consideration? I main a Guardian so I know playing a Burglar, especially a yellow line one is considerably different than what I am used to.