I've lived in the Denver metro (suburbs) for 7 years now and still love it. I moved here from a small city in the south.
- Large and growing tech community. Every year, I see job postings from new companies in the area. Google, FB, Apple, Amazon, Microsoft all have sattelite offices. Plenty of options to choose from if you're in development, IT, finance, etc. Lots of non-profit organizations as well. Good universities in Boulder, Denver, Golden, Fort Collins.
- Cost of living was certainly higher than my hometown, but much more reasonable than many coastal cities. Not sure how it compares to Chicago specifically. Housing and rents have been rising rapidly over the past few years. I've seen two bedroom appartments listed for around $1600 - $2200, but that's still a fraction of what we would have been paying in the bay area.
- Purple state, if the local politics matter to you. Blue in Denver/Boulder, red in Colorado Springs, more or less purple in the suburbs. There's a pretty broad spectrum of people to connect with. There have been quite a few measures on our state ballot that passed that I've been happy with.
- Traffic on I-25 and I-70 sucks during rush hour. It's a high growth area, so it seems to get worse every year. It's no worse than any other major metro area that I've visited though. Population density is quite low, so you often end up driving longer distances but with less congestion than you would have in many cities.
- Lots of outdoor activities in the mountains (but weekend traffic on I-70 is attrocious because everyone does this)--skiing, hiking, camping, etc. Lots of music, art, cultural events, museums downtown. Lots of good concerts at Red Rocks.
- There are large (and growing) populations of homeless people in Denver and Boulder. I don't think it's necessarily as bad as SF or NYC, but it has definitely been getting worse, especially as housing prices have risen. If you rent, it's easy to get kicked out for a missed payment. Heroin and opiate addiction is a problem throughout parts of the area.
- There are major sporting events here (Broncos, Rockies), but I've never been interested in attending them. I hear tickets are hard to get. Shrug.
- Weather is pretty nice, but it's quite dry. Forest fires can be a problem during the summers (mostly in the mountains), but that's the only kind of natural disaster that I've been worried about since I moved here. We can get a lot of snow during the winter, but the roads are well taken care of, and we get a lot of sunshine when it's not snowing. Makes for some excellent powdery ski conditions.
- Major airport (DIA) with direct flights to most other major airports in the US, which is nice. It was built out of the way, northeast of Denver, but it's a large airport and traffic isn't bad on the express way (toll road).
- Misc: Food and services usually seem pretty reasonable to me. Uber and Lyft are all over the place.
No place is perfect, and it's all about tradeoffs... but life is good and I have no plans to leave Colorado any time soon.