It's not uncommon to not see another carrier unless you're at an event with other open carriers. I've been carrying for a couple years (been looking for carriers for a year or two more than that) in the Springs and eastern towns now and I have only seen three other people open carrying anything. One was a single action revolver going in to the coop in Calhan to get feed, another was while I was working and I thought it inappropriate with so many people behind him in line to talk to him about his weapon, and the other was at the gas station and I only saw him briefly talking to one of the town cops as I drove out of the parking lot.
Three sightings of fellow carriers in three years. Whenever I go up north I do carry. I have a friend that lives in Aurora and, when time and money permits, I go out to lunch or dinner with him and his wife while armed. The only places I don't carry are the obvious ones and then to my aunts house, she is actively anti and at her age there's likely not going to be a change in judgement.
As for your cities of interest, I have carried in them when I am there. Going by my old neighborhood in Arvada (64th and Sheridan) I have stopped at many businesses in the complexes there, the Wal-Mart on 72nd, a few restaurants here and there, etc. I haven't had a single bad reaction while up in the Metro area.
Anyway, I hope this helps ease your mind that there are carriers around, but we're not so prevalent yet as to be noticeable or on every street.