OH I believe the one with the most outfits and fave design is indeed Rose!
It's funny bc I have the habit of changing her design to compensate the idea of her growth, and this she ended up having more outfits. Not to mention I also have designed her Halloween costumes I used to do every year, so that also counts 😅
In the end, yeah, a lot of her design are a fave for me, her current look is my all time favorite as of yet! ❣️

(Though I say this likely bc she's my long time OC lol)
If not Rose, my favorite OC design would be RR!Ériu, as she was a fave to have her wear pretty outfits, and bc she's an Elf OC, im a sucker for elves lol
I hope to believe WoL!Ériu would bring me the same joy 😊