Simple SHaco QoL. Everyone else has it, why not him?
Visible ult timer on clone Rito. This would be so incredibly helpful, you have no idea. Just start with that. If you do nothing else for Shaco, at least give him a timer on his clone so he knows when it's going to go boom like everyone else with a pet ability (except Azir, but at least with Azir you get an animation that starts to play a second or so before it vanishes).