I’d try to do El Tour if you can. There are multiple distances available. It’s typically a great ride, very well organized, no need to stop at intersections because they have traffic control at every single intersection. Plus, if you’re in town that weekend, might as well go for it! You’ll get to experience a lot of great parts of riding around Tucson, although they’ve changed the routes since I last rode it.
Definitely Mt Lemmon. Do the Saguaro National Park East loop. Ride Gates Pass over to the west side and ride through SNP West.
Actually, this list is pretty good:
Marsh Station Rd, Colossal Cave, and the Shootout route (don’t have to do the Shootout - just do the route) are also really good rides. Actually, I just looked at the routes for El Tour and they’ve moved a lot of it south - you miss out on a bunch of the northern routes. We used to ride out Oracle to the Biosphere 2 - I was going to suggest that you skip that because El Tour would cover a good chunk of it, but it turns out that’s no longer the case. In this case, I’d put Saddlebrooke on the list as well.