This is how I envision Tucson by 2050
with at least 1/3 of Tucson filled with 5-8 floor buildings outside downtown. Downtown will have taller buildings, of course. Maybe, another pocket of high rises at Kolb/I-10. In front of the buildings will be parking lots with parking meters/electric charging stations powered by solar panels. The modern street car will be the most popular mode of transportation. And Tucson will have an advance water collection system.
Since 2008, Tucson has required new commercial developments to meet at least half of their landscaping needs with harvested rainwater
As for GC Univ. locating "just south of the future Cushing Street" , that would be a first choice for me. It's not crazy at all, IMHO.
I used to live in Casa Grande and travel to Phoenix metro for work ( 2 year period ). I even know a few friends who travel to Phx from Tucson at least 3 times a week for work. So when that HSR gets implemented and Phx/Tucson would have their local rails positioned besides the HSR depot, that would pretty much help a lot of people out.