I like the "city university" name, but the acronym would be CUD. That's what a cow chews, plus it's too close to UCD.
No one outside of Denver knows the word Auraria, so if they named it anything like Auraria State, people would be forever answering the question, "where the hell is that?"
How about Mile High University? Everyone knows we're the Mile High City so people from out of town should get it pretty quickly (if not, they're idiots). It's catchy, no other school has a name anything like it, and MHU rolls off the tongue nicely.
It's settled! Mile High University!!