Details like product categories, additional costs for larger sizes, and size charts are largely lost when creating products to add to stores through the Rapid Product Creator. It would be a HUGE time saver to be able to retain most of that information when adding products to stores.

Edit to add:

Being able to set the cost of products and standard pricing for decoration that could carry over to the RPC would also be a big advantage. Not having to re-add categories and pricing to every single item would make store building MUCH more user friendly.