I used for long time AR/pistols so I may as well give you my experience
- clean state is too good to not use it, heal + cleanse, at least in Castle its golden
- same goes for AR healing passive Anima tipped bullets, use it instead then the pistol passives
- fullauto is one of the best AoE powers ingame, range and area of effect. It also only uses 3 energy
- high explosive grenade is good in scenarios becouse it also stuns, but if you dont have a CD head signet you may be better going with IG
- if you still fall short of healing just use the healing basic instead then Placed shot, even at 100% attack you will still heal yourself enough
That said if I remember it correctly (was long ago) I went Leeching Ray, HEG, Clean State, Fullauto, burst fire, dual shot and the cannon as gadget (it will single target interrupt and push away it right at AR range).