If Yuumi gets a non-interactive lane, she shouldn't scale well
I mean I dont know how else to say it. If Yuumi gets a free lane thanks to her non-interactive kit, then she should scale very poorly.
Every other enchanter in the game has to risk a bad lane phase to make it the late game, so Yuumi should be held to the same standard.
The main problem is that even if you shut down her ADC in lane, anyone else on Yuumi's team that's actually carrying will get the benefits of all those scaling adaptive bonuses from her.
The times where I manage to beat down Yuumi's marksman has always felt worthless, because even when my ADC is ahead, the powet delta isnt big enough to stop a fed Renetkon with a magical hat from destroying our backline.
She either gets a free lane OR she gets to scale. She cant have both. Especially for such a low skill-floor champion.