Having Romelu Lukaku was very good for Everton. It should have been a springboard for bigger and better things (the role we played in him becoming a monster on the world stage is a great recruitment tool), but we were a dumpster fire organizationally and are lucky the Prem was/is in such sad shape we weren't really punished.
There is no reason we should shy away from ambitious young players going forward. In truth, almost every player is similarly ambitious. Bainesy is one of a kind, a treasure to be, well, treasured.