I am in Missoula frequently on business. Hearing from my customers, there is a shortage of good people to hire. Yes, there are thousands of college students, but... I guess that means that one could find a job while going to school there. It might be retail, but...
I would suggest looking in the online version of the Missoula newspaper for both job listings and rentals. That should give you a real idea.
As a town, Missoula is getting big. Nowhere near Sacramento in terms of traffic, crime, etc., but big by Montana standards.
There are places to waterfowl hunt if you have time and are willing to drive 1 to 2 hours. But you are probably doing that in California to hunt overcrowded land (or paying for a lease). You won't have the bird concentration in MT that you have at the Sac Refuge System, but less (or un)crowded hunts reward those who put in the effort.
Good luck with your decision.