Colorado is absolutely beautiful in the summer months and the view on top of Aspen mountain is one of the best views in the world.
Before you go, go online and check out the live Webcams to make sure that it's clear.
Also, there's a small hike that you can do on you own up the mountain, it's a nice way to avoid the crowds and have some peaceful time for yourself.
You can purchase a pass 7 days in advance that gives you three days of unlimited gondola rides, 10 dollars restaurant credit and maroon bells bus tickets, it's a an amazing value at 30 bucks. One gondola ride is 27 bucks on its own without the pass.