Colorado has very little biglaw, as suggested above. These firms tend to hire either the top students from the local schools, or T14-ish people with strong ties (usually grew up/went to UG in Colorado, then went away for fancy LS and are coming back). If you don't have any ties, I'm not sure how they'll look at you (although spouse/SO with ties can be sufficient, if that's why you have to move). Then there are a range of midlaw commercial litigation firms, which you can probably ID through Martindale (but I'm afraid I don't know what those salaries are like). Also, keep in mind there are a couple of biglaw offices in Boulder, and Cooley has an office in Broomfield (suburb between Denver and Boulder).
Colorado biglaw is probably different from, say, NYC biglaw just because the legal community is so small; there's probably more mingling down the food chain, if that makes any sense. (That's a guess, though, since I don't know first hand anything about biglaw in NYC.) I think culturally/in terms of atmosphere, biglaw is pretty much biglaw wherever you go - it will depend more on the particular people in the particular firm/office you're looking at than on the fact that you're in Colorado. However, to the extent Colorado has any effect, I'd argue it would favor work/life balance, because Colorado's such an awesome place to live.
