Probably the Kirbyverse stuff he did for Topps in the 90s. It feels a lot like stuff he tossed off/didn’t really develop because, well, it’s exactly that.
Did you ever check out the KIRBY series Busiek, Herbert (and Ross kinda) did for Dynamite?

Being an internet refuge for Graeme McMillan
Probably the Kirbyverse stuff he did for Topps in the 90s. It feels a lot like stuff he tossed off/didn’t really develop because, well, it’s exactly that.
Did you ever check out the KIRBY series Busiek, Herbert (and Ross kinda) did for Dynamite?