All of the skill that is required to play Lee goes away as soon as he wardhops
Having to hit your Q from range to get into someone? LOL NO wardhop into melee range, aoe slow you into R stun (why is this even a thing) into Q-Q that you cant dodge and now you're dead, this is just faceroll, at this point even xin is a harder champion to play (since if he goes in a bad time he actually dies, unlike lee who just lol wardhops away).
And this is not even talking about his 350 (???) base ms, because a champion with that much mobility needs that much base ms just to run you down just in case he doesnt have wards to hop into and he misses his Q.
The best way to balance lee and make him actually take skill is by removing his ability to wardhop and reducing his base ms by 5 or 10, so he has to actually his Q's from range to do stuff.