The Arizona-Sonora Desert museum is a must. It was one of the best attractions I've been to. Its a museum, zoo, botanical garden and nature hike all in one. Its worth every penny.
https://www.desertmuseum.org/
If you want to catch an amazing sunset try Gates Pass.
Gates Pass is a quick ride from the city center. You’ll drive west on Speedway and up a long hill, which becomes Gates Pass Road. This road was built in the 1880s by Thomas Gates, a local pioneer, rancher and miner who wanted a shortcut between his land and the Tucson valley. Be aware that once you’re on Gates Pass Road, it becomes narrow and winding. There are several deep drop-offs, which is why the pass is not open to commercial traffic or vehicles more than 40 feet in length. There are several pullouts, but the main Gates Pass parking area will allow you to hike the nearby hills.
If you decide to do that I'd recommend this place for dinner...If you continue along Gates Pass Road south of the Tucson Mountains, you’ll meet up with Kinney Road, the route to Old Tucson for evening fun. If dinner is your goal, we recommend you head back toward the Tucson Valley and Speedway, turning left onto Silverbell Road. Hidden behind a McDonald’s® just off the intersection with Greasewood (named after the southwest native shrub), you’ll find a gem of an eatery called Teresa’s Mosaic Cafe. it was opened in 1984 by the Matais family, its excellent traditional food.
you’ll enjoy beautiful views as well as jugs of fresh homemade lemonade and baskets of tortillas. try the Huevos Rancheros, which were featured in a throwdown with Food Network’s Bobby Flay. Located at 2455 N. Silverbell Rd.; call 520.624.4512.
If you want to do some hiking or a really nice, easy scenic drive try
Saguaro National Park. Its comprised of two districts, East and West.
If you’re there early enough and want to make a day of it, check in at the Visitor Center for the park movie, exhibits, shopping and a detailed list of many special programs. Then head into the park via the Cactus Forest Loop drive for an eight-mile scenic tour of the Sonoran Desert. There are trailheads and pullouts to enjoy. Mica View is also a good place to catch a sunset (I though Gates Pass was better) there's a pullout complete with an easy desert trail and picnic area. There’s also a map to help put your viewing in perspective.
https://www.nps.gov/sagu/index.htm
If your downtown El Charro Cafe is excellent...
http://www.elcharrocafe.com/locations.asp
Here's a link to some of my pictures, they might help you decide on which places to visit and kind of show you what to expect.
https://www.flickr.com/photos/60907528@N02/albums/72157644513965519
If you have any questions just ask.
I loved Tucson.