I want to shoot off the bench primarily. Our range goes to 500yards but realistically if I could knock down a pig or two at the 300yd line it would be cool. Also some fun at the short range shooting offhand is in the plan as well.
Just looking at the STAG varmint. They any good ?
As for running and gunning my knees pretty much keep me to strolling and gunning. Lol
In that case, id recommend going longer in terms of barrel length. Minimum 16" but probably better would be an 18-20" with a quality barrel if most of your shooting is going to be at distance.
I don't have any personal experience with stag but if the internet is to be believed, I haven't come across any reason not to go the stag route.
In all honesty, I think your case suits perfect for what the AR does exceptionally well, modularity.
You could go the stag varmint route with its 24" barrel and use that as your primary bench/distance gun, and in the future if you decide stroll and gun or cqb shooting interests you, you can build a secondary upper with a shorter barrel so you're not "swingin ####" with a 24" long barrel.
At 1250 new for the stag varmint, you could easily budget a secondary upper to facilitate this, and probably still be under your 2k budget.
Just need a few decent optics, some ammo and a few dozen mags and you're all set with a quality, well made kit that will fit your needs and every possibility in between.