I have made over 100 mockups. I have narrowed it down to 16, and at this point do not trust my eyes at all. If you could look through this gallery and tell me which one(s) you like best, that would be super helpful.
http://jepphoto.com/proofs/nextonesamplecover/
Possibly relevant: this is what some of this kind of album look like in real life, which will maybe give you a little sense how the mockups translate to real life:


