What
The set OP posted is the standard set
Anyway, onto the RMT
Now, the first thing that stands out is Magnezone in this team. Magnezone's typically used in DragMag cores, because the win condition for the team is always centered on the dragons, and Zone needs to take Steels out ASAP so the dragons don't get cockblocked while attempting a sweep.
With balance teams though, your win condition changes with every battle. It severely limits Zone's usefulness, because you're now using him as utility instead of support. On top of this, the main things you're trying to beat with Zone, Scizor, Ferro, and Magnezone are already dealt with by Reflect Type Starmie, so it really makes Magnezone's role redundant
Because of this, I recommend running Choice Scarf Excadrill > Choice Scarf Magnezone
Excadrill @ Choice Scarf
Ability: Mold Breaker
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Earthquake
- Iron Head
- Rock Slide
- Toxic/Stealth Rocks/Filler
Scarf Excadrill is a nice alternative to Zone, it still deals with Fairies + M-Meta, while giving you an additional win condition against opposing HO teams. The final move is up in the air, toxic makes Exca a nice lure against Lando-T and Hippo, SR is obligatory hazards, etc
Aside from that, consider running Lead M-Aero > Wallbreaker Aero
Aerodactyl @ Aerodactylite
Ability: Pressure
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Taunt
- Stealth Rock
- Stone Edge
- Aqua Tail/U-Turn
Lead Aero gives you a much more consistent lead, without detracting too much from his original role. Taunt lets M-Aero wallbreak much more easily while also healping you block opposing SR leads/Defoggers. The choice for the fourth move is up in the air, Aqua Tail lets you check M-Diancie leads and rogue Hippos, while U-Turn gives you more pivoting power.
Finally, I'd recommend running Thunder Wave > Stealth Rocks on Clefable