I've also considered having ED-E broadcast New Vegas radio when he's in sandbox mode, I had a look and I think it's possible.
Also maybe an option to shut him down, so he drops to the ground. Why? Because I can! But he has issues with falling through the ground when he dies sometimes so maybe not.
Did you have any ideas for companion features? Preferably not combat related, you'll have Phalanx for that. Speaking of Phalanx, I'm not sure if it'll be compatible because the new separate sandbox package added to companions may conflict with edits the companions. We'll see.