Yeah, you're right. The ones I listed aren't that popular. A mainstream should be unique.
I have two more suggestions:
Dento's three little spikes and Iris' Godzilla-hair must certainly need some serious hair styling.
I like the idea of CordShipping, as pisces is joined by a string, but to my knowledge that's being suggested for Cheren/Bel...
Considering their conflicting outfits and personalities, as well as the talk of Pokemon Musicals, I think this fits.