While investigating what air stone is made of, I found an interesting tidbit;
"Oxygen in the air actually takes a long time (typically 90 seconds for an average sized bubble) to dissolve into the water via an airstone. It is the action of rising bubbles which causes water movement from the bottom of the aquarium, where oxygen levels will be lower, to the surface where the oxygen from the air can diffuse. The bubbling water surface actually has a larger surface area so allowing more oxygen to diffuse over time."
https://www.theaquariumwiki.com/Airstone
It's not even the bubbles that do the aeration, it's just the water movement mixing it around so it all gets to the surface at some point. You could probably just as well have a mixer of some sort in there with no bubbles at all, like a small water pump, though apparently the bubbles do increase surface area, but by how much? Probably not a huge amount. And by pumping air through the res like that you're also pumping in whatever is in that air and the heat, as the OP mentioned. Plus those air stone air pumps are noisy as hell. They're like miniature jackhammers. Drive ya nuts.