Wow those look really good! I'm doing my first rack of ribs today and can't wait to see how they turn out!
As for your resting question I found this in DM's sticky post about Baby Back Ribs:
"To check the ribs for doneness, we’re going to look for meat pullback from the bones (exposed ends of the bones), and also bark (the dark, chewy coating of the caramelized rub). A great trick I learned, from “Old Sarge” on the forum, is the “toothpick test.” Take a wooden toothpick, stick it in the meat next to a bone. You’ll feel the tenderness as you press it in. Then, give a little sideways pull away from the bone. If the meat gives, and the toothpick doesn’t break, they’re perfect! Pull them out, double-wrap in heavy-duty foil, and place them in a cooler until supper time! If they’re not quite done, give them another 20 minutes and try again. When they’re done, they don’t need to “rest,” like larger cuts of meat. Take them in, slice and serve! Resting, under a foil tent, while you get the side dishes ready, doesn’t hurt, though. They’ll still be nice and hot!"
So to me it looks like resting isn't a big deal like it is with say a brisket or pork butt although it's still probably a good idea for a short rest.