Would be great to add feature where customers (admins) can manage (view/edit) only specific categories. Most basically each root category could have role assigned (e.g. "Computers Manager) and customer needs to added to this role to be able to manage products/orders regarding role/category. Also advanced role system could hide core settings from admin section for some admins.
I know this is not small change but I think it would distinguishes this project from similar others as this feature can introduce more clients to one same webshop.
Daniel