KSR just changes your gaming experience with AR, I was going to change weapon before getting mine 
I am going to copy/paste what I told to another poster with similar problems about a scenarios AR/pistol build a few days ago, it should work for you too :
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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).
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IMO for soloing/scenarios dual shot is much better then unload as pistol power, as you want burst and not sustained damage. You will use pistol only to finish off mobs when they get close to you anyway, the biggest part of the job should be done by AR while they are far away.
That was for scenrios/solo, for the dps build absolutely ditch HE and go with IG, add lock&load (you never have enough energy with a KSR) and that leaves you with only 2 active ability free slots. One goes for the pistol power you choose and then you have to decide if you want an elite (trick shot) or one of the best skills ingame Kill Blind (with passive).
I noticed you made some confusion with passives too, you cant go without some mandatory ones like stability and slow burn (if you use IG). Forget the unload passive and the ground healing one, anima tipped bullets is much better. With KSR you should learn to live without explosive expert, at least in the dps build.
The tipycal AR dps passives are : stability, slow burn, secondary explosion, jungle style (only if you have room as its somehow bugged), then one or 2 slots for your secondary weapon passives.