I spent a few weeks in Colima, first touring around the area and then flying (thanks to Britton and Gabe for saving the day!). Top of my list was the Manatlán Biosphere reserve. This was a really nice drive that would be nice for camping. I also visited the nearby town Comala, which had a pretty main square with a few nice restaurants and cafes.
We arranged a trip to Nevado de Colima with a few people from Guadalajara. This is a extinct volcano that stands 2,720 m tall. From the top you can see the Volcán de Fuego, which is still active. It was a beautiful trip and well worth the drive.
I didn’t spend too much time exploring Colima, but from what I experienced it seems like a calm and fun city.