Why do you feel you need a better listing method?
I have over 12,000 items listed, a majority books. A significant portion pre-ISBN.
Any listing software would be a disaster for me given the state of the Amazon catalog and its myriad duplicate, incomplete and incorrect detail pages.
Greater than 50% of the existing pages I list on need correction. Manual selection of which of the duplicate pages is essential. The page with the ISBN is not necessarily the best-selling page when there are duplicates - the page with the best picture often is.
For books without existing detail pages, some listing software requires you create the page without an actual offer and then create the offer through that software. IMO very inefficient, it takes me seconds to add an offer.
If you motivation is repricing, you should target your hunt to something which reprices without changing your listing methods.
If its multivenue sales, that leaves you in the morass, and you become a part of the duplicate page problem if you attempt to optimize your listings for venues like Ebay.