Contrary to popular belief, I can be a bit of both. Waking up early is no problem for me, and I actually quite prefer it. I'm more motivated to do something earlier on in the day than wait to do it later at night. However, I can stay up pretty late if I wanted to, I just choose not to. Sleep is too important in my opinion and I rather not lose it while I've got it.
I would say my mind is more active at night before bed, but let's be honest, my mind is like a train that won't stop. It just keeps going. There are no breaks in there.