This is based simply on my results of the storyline playthrough of White, but why, WHY has it not been mentioned to put Attract on any of these sets? Yes, I know it's pretty limited in use, as it only effects 1 gender out of the possible three, but most people don't pay that much attention to genders unless it's absolutely necessary. It's a bit of a gimmic and a risk, but in my experiance, ABSOLUTELY worth it. Attract AND stun-spore pretty much assures that they will never, EVER land a hit on you again, and makes them definitely think twice about off-gender switch-ins(especially if you troll hardcore and have something else with attract of whatever gender Whimsicott isn't).
I mean, to actually break it down, Stun Spore is better long-term but Attract is more likely to net a critical instant-switch. Attract is 100% accurate, but Stun Spore isn't gender dependant. Stun Spore lowers their speed, but Attract has a 50% chance of them doing nothing. Attract ultimately wins out, I think, once you factor that it can stack WITH stun-spore, as well as ANY other status, such as Toxic or Burn; that it's less expected, prepaired for, and resisted; and is altogether just really amusing.