Yeah, it depends on how you are using this database. For instance, I'm not worrying about the grading of the book, whether its been bagged or boxed, or whether I've read it already, I just want a list of books I have. The biggest hurdle of this (and any comics) database is when you have to enter a LOT of books (the initial entry), and there are a bunch of places where it could be made much more efficient. A couple of other ways to speed up rapid data entry:
1) "Next issue" goes to the actual next issue, and skips variants. Looking at variants should be a different button.
2) On this line, seeing all the variants on a single page (with a single-click "add to my collection" under each of them) might be helpful.
3) Some way of quickly jumping to different "types" under a given title -- e.g. "Individual issues", "TPBs", "Annuals" -- something like that. For those of us who read books that have been around for awhile (Superman, Batman, 2000 A.D.) its quite a scroll to get to those other types of books.
4) Add a range of issues should be a text box ON each page rather than a link taking you to another page. This way the range can be quickly entered, and you don't have to hit back a few times to continue entering.