Remove Reshiram from the game entirely. I'm so fucking tired of seeing Reshiram and Cresselia.
They really should've nerfed Cressy alongside Reshiram when they had the chance. Reduce the healing and synergy gains, make it charge slower, anything really. Another nerf to Reshiram wouldn't be too bad either. Maybe make it come out slower so it's not as amazing as a tool for getting people off of you. Getting rid of the attack debuff would also be nice. I mean, it basically has no downsides seeing as you can negate the long charge time.