Blitzcrank Rework proposal

Meddler was talking to someone about another champion using heat. I have an idea about a possible Blitzcrank rework that could use heat, without being a copy of Rumble. Lets start with his passive.

New Passive: Blitzcrank now builds up heat after casting spells, at 100% heat Blitz will overheat, gaining new ablities and bonus magic damage to his basic attacks. 10% Cooldown

Q Pull/Punch (Overheated): Blitzcrank shoots his fist knocking the first unit hit back then exploding, dealing aoe magic damage and is stunned if they hit a wall

W Spell Barrier/ Blitzcrank gains a shield based on his maximum health (or AP), when Blitzcrank is below 20% health the barrier will reflect any projectile W Overdrive (Overheated) Blitzcrank gains X movement speed and attack speed for the entire duration of Overheat. (Or X seconds)

E Power Fist/Power Slam (Overheated) Blitzcranks next three basic attacks will slam the target into the ground, rooting them for 1 second.

R Static Field/Static Boom (Overheated) Passive: Every 3 seconds, Blitzcrank emits a small explosion around him dealing magic damage within 400 range Active: Blitzcrank creates a wide range explosion, dealing magic damage to nearby enemies within 800 range and burning them for 1.5 seconds. Static Boom's passive is only enabled when the active is on cooldown.

The idea around this kit is to play defensively until you are overheated then that is when you get to go on a rampage, the damage and cooldown of the spells are debatable of course. Any thoughts?