90VG this is the best Vietnamese place in Tucson. The owner/cook is first generation I think, but he taught us all how to pronounce Pho (my son loves it) and they're stuff is excellent: Ha Long Bay. Pho 88 if you want authentic (we are talking pickled chicken feet and etc. My brother dragged me there until I finally started to enjoy it... Not for the faint of heart, LOL). It's ah, well, earthy Vietnamese.
Best Italian (again authentic but it is SO GOOD) Guiseppe's Italian Restaurant. Bit on the pricy side.
Gee's Garden is probably the best Chinese food in Tucson that I've found (and they do Dim Sum) but also great carry out... They have a huge banquet area for Dim sum and unless you are doing that I kind of recommend takeout-- it's carpeted and smells a bit like Dim Sum all the time

Korea House (if you like Korean food) again on the "authentic" side and the interior is ugly but they do pretty good Korean...
Indian Food: Sher-E Punjab Homestyle Cuisine (it's in this super run-down shopping center on Grant Road, but the food itself is fantastic and lots of options, as it does several styles of Indian Cuisine. Again, the décor is... Well, it's run down a bit, but I haven't found an Indian Restaurant in Tucson that's better...

Finally, PIZZA. Magpie's is voted #1 and is down on 4th avenue and you can see how the RUINED the old trolley by turning it into a vaguely frightening tram.... Which now goes further than up and down 4th. I still hate it.
I prefer Upper Crust Pizza (actually RIGHT NEXT DOOR) to the dreaded Karuna's but honestly their pizza is some of the best in Tucson. They hipstered it up, so be prepared to wait if you are going during a hipster time period, but it's great pizza!
Hope some of this helps. Keep in mind I've been here 10 years now so it may not compare to some of your locations, but I'd say this is a reasonable start.
If you like Mexican food (I don't) be prepared for "authentic" Mexican for the most part, which if I ever have to eat another bowl of menudo in my life, I will be very very sad (was always eating it at work when we'd have pot lucks and it was so NOT awesome) but even the Taco bells around here are often unusually spicy or otherwise slightly changed.... I actually don't mind that, but I do NOT go out of my way to eat Mexican in Tucson, so I'm probably no use to you there.
Good luck, have fun and safe travels if you visit!
Anna