Veigar Passive Buff

So right now, as we all know, has an extremely useless passive that gives you extra mana regen in the tenths. Since Veigar lacks a lot of mobility and can only "run" with flash or his stun, I think aside to the mana regen he gains with his passive, he also gains 0.2% base movement speed for each 1% mana missing. That would be +68 movement speed for 0% mana which would be next to impossible because mana regen is still a thing. Just a little idea that I thought would be great for increasing mobility and buffing 's nearly useless passive.

Just my ideas. Bai