We lived in Utah for 20 years, but not that high up. But there were some beautiful gardens in Park City, and some of the other towns at higher altitude there.
I'd advise before you plant anything, take a walk around your neighborhood and see what other people are having success with. There are other considerations besides just the cold, snow and foot traffic. You want plants that won't be devoured by animals like deer and moose, and can take the freeze/thaw cycles that happen in fall and spring as well.
Sometimes you can transplant or collect seeds from local wildflowers and low growing plants to use as groundcover.
Pavers might be very slippery and difficult to shovel or keep cleared in winter. Again look at what the local people, and also businesses close by have used.
