I'm building my own app this time, so I'm changing some stuff up as I go, which is really forcing me to understand what I'm doing. When I finish, I plan to go back through again to really customize my app. For instance, instead of using gravatar for profile pictures, I want to use CarrierWave, so that my users won't have to sign up for a different site to have a profile pic.
As much as I'm enjoying Rails and learning the backend, though, I'm really looking forward to customizing the CSS on this and adding my own look and feel to this app. I probably should take some time and just do some brainstorming on this and taking notes.