Sorry for being unclear. Muk is the one to be taken out; he and Rotom-H share the Genesect counter role, but Rotom-H is better in the sense that checks more things (Tornadus, Sun teams, etc), is not weak to Ground, and has a superior moveset that allows way more utility than Muk. Loss of fighting resistance doesn't matter that much if you use Starmie, since you'd have two Psychic types that can easily sponge Fighting attacks (and hopefully kill them, especially in Gothitelle's case).
Not accepting rating requests anymore. Sorry!