how about temporary invulnerability to fall damage as part of mcmmo like superbreaker style?
As wheatley suggests, this is already somewhat of a feature with the roll/graceful roll abilities as part of acrobatics in mcMMO already. Both by just naturally falling plus if you sneak as you're falling there is a chance for the damage to be reduced. If you do
/acrobatics in-game it explains it a little more.