NO model of the Q7 cools any more quickly than any other. What they ALL need is a way to circulate filtered air on the back of the primary mirror.
The control box is a REALLY cute feature on the 3.5, but is in my experience unnecessary on the 7. What most of us want is a big honker top quality 2" diagonal on the back of a 7 that can accept ANY eyepiece, camera, video cam, binoviewer, or whatever you want. At the FL of the 7, the control box finder is much less desirable that a finder scope, telrad, or laser finder up top. And the control box barlow, while convenient, is nowhere near the quality of a good TV Powermate, Vernonscope Dakins, or whatever suits your fancy. Most of us who own a Q7 want to load the back with the stuff we CAN'T load on the back of the 3.5 - and the control box is just extra weight and drag, and takes up valuable back focus that is often needed elsewhere.
The control box on the 3.5 helps make it the most portable, complete, high quality "Observatory in a Box " ever made, and I wouldn't change anything about that. But you don't buy a Q7 for convenience. You buy it for the power that comes from all that extra aperture up front with great Mak-Cass optics behind it. The Astro 7 is just a more direct approach for those of us who want to customize what we want to use on the back of the scope - and there is a lot out there to choose from.
At least, that's how I see it after years of experience. I'm sure there are other Q7 owners that feel differently, and I respect their well-founded viewpoint.