This is a major thread hijack given the OP likely could care less about the quality of beer in the destination city.
My brother lives in Denver. I like it down there a bunch and try and make a GABF pilgrimage every other year. The availability of good beers in Denver is fantastic. That said, Connor is right, none of the breweries you named are top 10 by any metric. California is home to a better beer culture and a measurable amount of better brews. If I were going to move somewhere in North America solely based on where I could drink the "best" beer, Denver wouldnt make my top 5.
California may be home to some of those beers like the Pliny family that people swoon over but the concentration of breweries in CA is very spread out in relation to the front range of CO, so its hard to hit the good spots in a day like you can in CO, plus California sucks. You're right access to beer out here is great and I am sitting in San Francisco airport right now waiting to go to Hawaii with a suitcase of beer we cant get there haha.
http://www.portlandbeer.org/breweries/map/
I'd give the nod to Portland in that horse race.
I looked at moving to Denver for my career several years back. Great people, great sun, centrally located… But the cons were suburb sprawl hell, and mountain access that clogs badly every weekend. In the end, I couldn't see leaving Vancouver for it. But if you're coming from Fort Mac, it's an upgrade (IMO).
I live in a small town between Denver and Boulder and its nice, yeah there is some nasty urban sprawl but thats mostly east and south and easily avoidable. Mountain access can get clogged depending on where you go but with proper planning it can also be avoided. I went to aspen over this past President's day weekend and maybe spent 15 minutes in traffic, which isn't bad in my book. One more good thing about the Denver area is that there is biking/dirt biking year round too.
jake has come through for me before, I fully suspect he is just trying to find all his clothes and finishing up breakfast