they should just give his passive a massive temporary armour and mag resist buff. this would help get him out of those sticky times when the enemy just uses your down time to reposition and kill you again, and at the same time discourages team fights from throwing down on top of you knowing you will be beefier when you come back up.
going the armour/mag resist route keeps it from giving him too much sustain by increasing the heal %.
his air smash needs to just have a lower cooldown traded for some of its damage. just enough to let him initiate with it and after 3-4 seconds use it to disengage. he does have wings after all.