Visiting Missoula today as part of a three-week tour of Intermountain West bike paths and rail-to-trails, I experienced much of the excellent bike/ped infrastructure here, including several bike/ped-only bridges over the Clark Fork, and some fine overpass/underpass options at busy roads.
It can be done.
Something else that Missoula does is properly sign the damn trails.

Here we see the standard wayfinding present, distinguished in this case as the starting point for the Riverfront, Bitterroot, and Milwaukee trails. This confluence via roundabout is quite lovely and immediately has the visitor checking out real estate prices. These markers exist at every tenth of a mile in each direction of the three trails.
It can be done. And not just in Missoula.