No because I don't main people based on superficial things like palettes.
It's no more superficial than picking your favorite character or picking whoever you're told is stronger.
Why should it matter what reason anyone chooses who they want to play as?
I absolutely hate Yosuke, but because he has an Eikichi alt I'll probably take him for a few spins (not gonna main him though)
EDIT: To actually talk about the TC's question, I don't have any moments like that with the GG or BB alts because...well...I don't play either of those games, but I did have a moment like that with Akihiko having a Takaya alt. Also, while I wasn't the hugest fan of either character, I think Yukiko as Chidori and her Persona as Medea is the best looking alt color. It works so well.
Don't forget to check out my MegaTen themed webcomics at http://www.drunkduck.com/user/Strain42/