Option One:

1. New User Registers (you will want to set registration to Private)
2. You verify their account is good.
3. You build them their custom page and on Page Settings add their UserName to the Permissions area and provide them with the required access.

Option Two:

1. New User Registers (you will want to set registration to Private)
2. You verify their account is good.
3. You Add a new page and use an existing page as a template and then change it is required for them and Page Settings add their UserName to the Permissions area and provide them with the required access.

I do much the same and am finding it does work well... also with custom text as well depending on roles, to go along side access by user.

With the hiding modules with the check box (top right) it makes it fairly easy to manage quite a few, especially as I include user info in the module title and keep them organised alphabetically. This is the longest delay actually when there are new users as I have been unable to move modules simply by dragging and only using the settings and moving down/up a module at a time.

I know for downloads I had found one that has access control for each file/item, I think from memory it was US$90 or so, from memory but if you are interest in that as an option I will find out where I saw it.  For now I am using mulitple module instances which is ok.

Considering the different pages, and users accessing these pages I was concerned this would make admin menus very messy if the pages were included in the menu... so I've avoided this for now.  Anyone else had different experiences on it please let me know!