Fully-Interacted?

I'm greatly enjoying the new clickback button, but I've got an idea for the interaction section: is it possible to have it display if you've interacted with all of a farm's Pokémon? I've tried to click back everyone, but sometimes I receive more clicks than the other person has Pokémon, and these names will always be (among the) first in the "Both" section. Without moving them, is there a way to change the link's background?

I'm not sure how the interactions are coded or stored, but this would most likely cause lag, since every time the interactions page is loaded it would have to check how many Pokemon a user has, for every user on their list.

Locking and moving to completed since it's now view-able on user pages.