Blitzcrank's New Passive: After taking damage by enemy champion (or a monster), Blitzcrank marks the enemy champion. Until Blitzcrank gets damage by another champion, he takes reduced damage by the marked enemy. He can mark an enemy every 5 seconds.
Blitzcrank's Q is unchanged.
Blitzcrank's New W: Blitzcrank gets massive bonus movement speed. After short delay, the bonus movement speed ''dissapears'', but he still has bonus movement speed and his next basic attacks will knockup the target. After the knockup, Blitzcrank is slowed by X% for short delay (It's just the old W and the old E combined, after the knockup Blitz is slowed like the slow when his old W finishes).
Blitzcrank's E (totally changed):
Passive: Blitzcrank stores the reduced damage by his passive (as debuff). The stored ''points'' dissapear after 30 seconds of no taking damage.
Active: Blitzcrank shields himself, scaling with AP, HP and the reduced damage by the passive.
Blitzcrank's R: Still the same, just has really short delay between cast and action (like Darius' Q) (Blitzcrank's sneared during the delay). Blitzcrank's ult can't be canceled by any CC and Blitzcrank takes reduced damage by every enemy during the short delay.
I just want to say that:
1. It's suggestion, so everything is unbalanced and has no scales.
2. I don't speak English very well.