I thought about this a while ago.

Everyone wants a Pro streamline looking store.

But do you really need to?

Best thing would be to keep your book categories and put the other items in the "Other" category.

or 

You can sort of have a few Stores in one.

Just name your Categories as a store.

I think sellers are to fussy and over think the layouts to much.

Im pretty sure Most of my sales came from the main search or browsed listings without anyone visiting my store.