Actually I’m being a little rhetorical, here. My PSA stainless freedom barrel with a 1:7 twist is quite acceptable @1-1/2” groups. I just don’t like the long, hard, gritty trigger pull (unlike SgtBob and Ermey!)I just want a nice soft, liberal trigger pull like on my bolt action hunting rifles.
A good roundup/review of available drop in triggers.
http://www.thetruthaboutguns.com/2016/04/jeremy-s/ar-15-drop-in-trigger-roundup/
I assume you don’t want too much of a hair trigger on something that is essentially a battle rifle/self-defense carbine.