My final buff idea for Mr Fantastic.
Reflexive Rubber:
When in Reflexive Rubber mode you are no longer slowed down.
Ultimate Ability:
You now gain 50 over-health on cast and per bounce.
Flexible Elongation: New Effect:
When dashing to Allies over-health can be carried over to multiple Allies with the spell field.
When dashing to Enemies inflict 10% anti-heal which decays after 5 seconds. Can be carried to multiple Enemies with the spell field. Can be stacked.
(Numbers can be changed of course i just went with what felt right)
Edit:
New Passive: You now deal more damage against over-health, shields and deployables.