Koggy doesn't need true damage
He doesn't need hard CC.
He doesn't need a displacement.
He doesn't need a movespeed boost.
Koggy certainly doesn't need any buffs to his ideal-use case of extreme long range pew pew since he's already good at the LCS level despite his non-existent pick-rate in Solo.
What Koggy needs is a heightened ability to eat people's faces when they get close to him. His Innate already does this (sort of). But why not make it help him out against close range targets when he's still alive instead of making it a pure revenge-kill tool that everyone in League of Mobility can just dash away from?
We can even tie it in to his lore. Instead of spitting at close range, have him bite a chunk out of folks who get up in his face. Give said biting some kind of bonus effect to help Koggy peel for himself in the only way he knows how, with overwhelming damage.