We have been running a Xero integration for 2 years with Neto. We have been in contact with support numerous times and looked at all the suggestions in the ideas map, many people have the same unresolved issues we do.
What Neto could do, to make it a unique platform in the Aus/NZ marketplace, is integrate its own accounting platform.
Crazy you say?
This business of managing API's is for the birds. I'm not suggesting to build a platform from scratch but to buy a small cloud based accounting business and integrate it into Neto. Than get to work on the inventory management issues.
Neto can't compete with Shopify so stop trying to. Offer a unique product.