I've never seen a 3.5yr old with snout that round, stubby, and full. I'm sticking with my 4.5yr old "guess".
Only take him if he's a trophy in your eyes. Culling him won't do a whole lot to change the genes...besides he has decent beams, and nice mass...say he breeds a doe that has a narrow, thin, racked 12pter bloodline and the buck fawn turns into maternal g-dad's points, with paternal g-dad's mass and beam length?
In other words, his genetics could suck a whole lot more than just the fact he's only a 6pt.
Based on his face and his body, I'd still zing him. You are right though, if you have other "hit-listers" and your "game-time" decision is put to work in early October, I can't honestly say I'd take him out at that time.