Man, the problem with that is there really isn't an airport nearby, at least not that I recognize. Your best bet is probably Flagstaff, but you'd have to get a ZED on US Airways, and that also requires 6 months seniority. SGU isn't too bad, but that's where SkyWest's headquarters are. You're going to get a lot of nonrevs, and a few seats held on the EMB-120s for weight restriction. Maybe CDC. Don't worry about what time of year is best, especially for places like that. Just check loads and if it seems reasonable, do it.

And remember, getting from MSP-SLC has more options than you think. If you can't get a nonstop, look into intermediate cities, like RAP or something. Sometimes you can keep the same plane going through. I did that once with OMA, since I worked for OO and my DL benefits only extended to OO-operated flights since I didn't touch the Delta system.