The ACL system in VM seems to be totally lame, we need admins with less access rights for one vendor - not several vendors...
I'm quite sure the majority of the stores running VM and other OS carts are having one vendor/seller only, but they do have more than one "employees" handling orders etc. They can't all be vendors or system/super admins to be able to handle the orders??
From what I can see you now has to make a new admin group under 'System Admin', and then having to add restrictions, instead of starting with less access and add what's needed. This because 'System Admin' is the lowest access level in Joomla witch is making the user 'storeadmin' in VM...