I'd cull the current team of janitors and mods and appoint people who know the board inside and out and have been on it for a while.
Remove blatant genwar threads. Genwar arguments within threads would be left alone, since that's not as cancerous.
Waifu and husbando threads are to be left alone. They're a staple of many boards and they've been on /vp/ since its conception.
Delete anti-Smogon shitposting. Emphasis on SHITposting. I wouldn't delete every post that criticizes Smogon, but delete posts such as "yeah I'd say the Smogonfags are fucking retarded". They never bring about any good discussion and just encourage people to continue making similar shitposting. If you are against this, point me to a thread where this is not the case.
Phox Friday, Gardevoir threads, and all their variants would no longer be deleted. Cropped porn would be allowed to remain, even if it accompanies suggestive comments about Pokémon. Blatant porn and blatant suggestive shit would not be allowed (obviously)
Three day ban for any HG thread. One week ban stealth HG threads and relocation of every HG thread to
>>>/trash/.
Remove giveaway threads. They belong on /wfg/.
Create a sticky giving a brief overview of the rules.
Probably missing a lot of stuff but that's my approach. Want to be laid-back and try to improve board quality without being too banhappy.