If you can manage to get to Denver somehow, Icelandair has really damn cheap flights to most of Europe. One way ticket for $550-$600. Lowest I found was $384 to Berlin on a Wednesday in May. Ryanair should never be flown for more than an hour or three, as it's one of the worst airline experiences.
I planning to fly Icelandair to England this summer. They let you choose up to a week layover in Iceland, so I thought it would be a cool way to take a few day detour to Reykjavik on y way to a necessary trio to the UK. I'm not sure I'd go otherwise, but it looks like a beautiful country. Have you flown them before? If so, is it a decent way to travel?
I picked Icelandair for my parents when they came to visit me in Canada. On the way back they did a two day layover. I recommend it if you're at all interested in visiting Iceland. Only big downsides are the times of arrival and departure, which are usually really early in the morning, and the rather expensive hotels. Transfers on Reykyavik are quick (1 to 2 hrs) on the way back.