Luden's Echo

My only thing about patch 5.13 (the veigar ult particle growth is my favorite listed change i've EVER SEEN in patch notes!) is the newest AP buy to hit the rift. You say your intention is to move Luden's into a mobility/casting powerhouse item right? Instead of giving an invisible stat to mages (a %movespeed boos is pretty huge, but not easily noticed by the enemy) - why don't you give it a similar effect to Furor enchant? Upon casting (this one might be too OP, not sure) or upon hitting a spell (higher % for single target) THEN you grant the same 10% movespeed boost? It becomes more obvious why your opponent is outrunning you, plus it pushes the "I cast a lot and move a lot" mentality, rather than "I just got free movespeed on top of this huge AP item i just bought."

Thoughts?