As much as I disliked the Gase hire, whoever is hired should have the exact same philosophy as Gase regarding roster building/management.
Everything that has happened previously is irrelevant. Right now, the entire focus of this team needs to be getting Gase the players he feels best help execute his vision for the team. Normally, I'd want the GM to have the vision and let him hire a coach that agrees with it, but the milk is spilled, so do it the other way around this time.
If it doesn't work out, this team will need a true scorched earth rebuild anyway. So Johnson needs to go all in with the choices he's already made. Power play or not, this is Gase's team now.