ITT: You can change the Kanto dex but you can't touch (remove or add):
Legendary
Starters
Mega evos
Forms
Mythical
US
Paradoxs
Dyna/Gigas
you can't remove:
Gyarados
Snorlax
Eeveelutions
You can't add:
Pure Dark Steel OR fairy types or any dual types that are combination of those two like Grimsnarl or Bisharp or Magearna

Rate and discuss what would change for better or worse