Based on the schools you’ve listed so far, I’d suggest taking a look at Rice, and as you’re looking for a few more “likely” schools, I’d strongly suggest William & Mary. My twins were pretty picky about their schools, and their list of reaches looked a lot like your son’s, and they’ll be heading to W&M in the fall.
“D&D DM / church youth group leader / district quiz bowl champion” pretty much describes the ur-student at William & Mary. Basically: super-friendly, super-smart.
W&M would fit into that “looking for a target” desire. From my research this year, here’s a list of all of the mid-size (4k–9k undergrads) schools that Fiske rates academically as 4/4.5/5, along with their admit rates. (I’ve bolded the ones you’ve already mentioned as being on your list.) Though all of the schools listed on the spreadsheet (and elsewhere in this thread!) are worth considering, from a “top academics with an accessible admit rate” perspective, you can see how W&M is in unique territory, and from what you’ve described of your son, I think the campus culture would resonate a lot.
