Just wanna recommend a few QoL changes that could be implemented to help Yuumi feel more of a natural playstyle.
1.) Allow the use of a keybind outside of the skill key to automatically detach her from an ally into free roam mode (and not have you get stopped because "out of range" errors). And I mean detach detach, not try to jump to an ally, especially since her passive warrants some need for basic attack weaving.
2.) Allow empowered Q missile to be a small AoE (Karthas q size?). It already has a small detonation in the animation but to have this only hit 1 person doesn't feel really impactful.
3.) Make it more obvious who you're attached to. I cannot stress enough the amount of times that I have lost track of who I'm attached to or if I'm in free roam in the middle of a teamfight because there's way too much to keep track of. If there could be a way to make it obvious who ur attached to other than just a tiny icon near their healthbar, that would help TREMENDOUSLY.
4.) Allow ult to be cancelled.