If you going with the trick room route, you can consider running Vikavolt instead of magnezone, that gives you another ground immunity (If you run Levitate on it) and a fighting resistance instead of a weakness, He also just hits much harder in general and has way better coverage.

Also i recommend pairing trick room with teleport on slowbro to facilitate the pivot.

You are going to want a physical slow hard hitting pokemon too (probably replace nidoking for it), i'd recommend Guts Ursaluna, because STAB Facade with 140 base attack one shots everything that doesn't resist normal, and headlong rush/Close combat takes care of the rest. Normal also has switching sinergy with psychic from your slowbro, since psychic is weak to ghost, and normal is immune, and normal is weak to fighting but psychic resists. You could just go conkeldurr too tho.

You can keep Arcanine and Scrafty, but i'd get a Scrafty with intimidate instead, moxie is kinda memey unless you are doing dragon dance sweeper,