Well, I think you're definitely going to want Ambush, Critical Power, and Blindsiding.
With no dodge or evasion, you're going to be getting hit a lot. Really an awful lot. So you probably should get Paranoia so you don't take as many crits. You may also want both Grenadier and Quick Tinkering to help keep enemies at bay.
Both Nimble and Sprint should be helpful.
I know you said you wanted to go sniper/pistol, but with low Dex, pistol can't really perform at its peak. If you can find it in your character concept to go sniper/AR, then you'd want Opportunist, Suppressive Fire, Concentrated Fire, and Commando. If not, then maybe Kneecap Shot and perhaps Point Shot, so you've got some decent special attacks with the pistol.