Remove Stall, it's the reason the only official formats are 3 v 3 and 4 v 4 doubles:
Healing moves like Roost, Wish and Recover, only heal by 40%. Leftovers only heal by 1/20. Regenerator only heals by 20%. Eviolite only raises Def/Sp.Def by 10%. Poison Heal only heals by 1/12. Grassy Terrain, Aqua Ring and Ingrain only heal by 1/20. Rest keeps Pokemon asleep for 1 extra turn. Also all of the moves mentioned have their PP lowered to 5.
Remove Endless Battles:
Leppa Berry cannot be revived with Recycle or Harvest. And to remove endless switching, make players only be able to switch a max 40 times per battle.
Lower Moves PP:
All non damaging moves with PP over 10 should be lowered to 10. All damaging moves with PP over 20 should be lowered to 20.
Nerf Baton Pass:
Baton Pass now only passes on stat boosts, so you can't pass substitute or Ingrain. Also if a Pokemon was switched in with Baton Pass, whenever that Pokemon tries to use Baton Pass itself it will fail.
Nerf Shadow Tag/Arena Trap:
Remove them from all Pokemon except Wynaut, Wobbuffet and Trapinch.
Nerf Evasion:
Evasion only lowers opponent's accuracy by half as much as it currently does.
That's enough.
