Standardized Stores for Multisite

I am having trouble coming up with a solution to this problem:

I have set up a multisite network and have it so all users who create their own site will have their own identical store-page. The missing piece however, is a backend form for users to fill out that will populate their own store-page with their information. I have restricted site owners from being able to edit the page because then the pages wouldn’t all look the same. Does anyone know of anything like this? It is almost like an advanced profile form for site owners. Help is sincerely appreciated.