Let's talk about Youmuu's Ghostblade
So its received countless nerfs through the past couple patches... and it's still good. You buy YGB to reposition easier in fights and to run away/kite, and that's the issue here. Nerfing the damage and removing the attack speed didn't do squat it's still doing it's job too well.
Idea: Give back the attack speed. Rather than making it a medium MS boost for a drawn out duration, making it a QUICK BURST of movement speed, and give attack speed for a certain number of autos or something (like 6 autos let's say) to make it the item that it should be. A burst oriented, quick powerspike item, that falls off in favor of other items in the late game.
Need to reposition quickly to align a skillshot? Want to take down an enemy quickly, but with its limits? Just BARELY out of range to cast that spell? YGB is the answer. Not this weird jack-of-all-trades-master-of-none item.
I might have a slight bias because I am a Twitch main and miss the old YGB rush build, but trust me this would be healthier overall I think.