Everything you listed in your positives for Rice Eccles is great for Utah fans, but doesn't mean much to others.
Michigan may be a dump, but it is considered a must visit stadium by all college football fans. Utah simply is not considered a must visit stadium, and it may never be. BYU on the other hand does make a lot of lists simply because of the back drop, if for no other reason.
Rice Eccles simply is not on other college football fan's bucket list as a must see.
And that is what I use as my reasoning. Would I go out of my way to see a game there?