Colorado is such a beautiful state, there is plenty to see. I am a new flyer and I'm still searching for good places, too. I just did a good one in Rollins Pass/Moffat road, all along 119 from Blackhawk to Estes Park has good views. 93 from Boulder to Golden has some cool spots. North Table Mountain is on my list to try. Any National Forrest is good. Highway 50 from Pueblo out through Canon City and Salida is a great drive, I want to go out that way soon, too.
All Denver parks have a drone ban, you can't launch in any Denver park (Red Rocks is in Morrison, but is still a Denver Park). Near Denver Airport is restricted of course, and there is an airport in Broomfield that restricts a good chunk just south of Boulder. AirMap shows a ton of little airfields all over, probably mostly no tower kind of things. I'm still not clear on those, I think you just call and let them know you're flying, right?