You'll have a hard time getting roadmap information on this forum - best to reach out internally to the ISE PM.
Has your customer considered using RBAC? You can create some Data Access restrictions that will ensure that only the right people can edit their allowed devices.
It doesn't seem possible to HIDE the non-allowed devices - but you can enforce adds/changes to be made.
e.g. below the user group member can only edit the devices that are in location IPTEL-LOCATION-MILTON
If they try editing any other devices they get a GUI error.
It's not perfect, but potentially useful. You can hide menu items though - but in a multi-tenanted environment the data hiding is probably more important. It seems like a bug to me that you can specify "No access" to ertain data elements, but ISE will still display the data.
