There's no rule that says a carbine-length AR can't also be a great scoped shooter. Here's one my newer toys, an R-15 carbine with a Leupy VX-3 3.5-10 X 50. Wouldn't shoot so great with the crappy trigger it came with, but it routinely shoots very tight groups since I dropped in Timney's AR trigger. It's now one of my favorite predator rifles.
I bought that same Rem. R-15 you have 2 years ago. Mine has a Leupold 3X9 on it & shoots 1/2" 5-shot MOA groups @ 100yds.
It's my Favorite coyote rifle here in North Texas.
BTW, either y'all got a hell of a lotta rain around San Antonio, or that's an old jpeg. We are dryer than a witch's tit here in northern TX...