Well, I'm currently plot resetting for Mira and she's put her plot in the worst places possible five times in the past hour, but out of the ones I've actually had I like Cherry the best. I liked Frita a lot too though.
My personal favorites are Shari and Mira. Other cute ones are Cherry, Fuschia, or if you like the more rough-around-the-edges character designs, Katt or Hazel. 'v'
There is no best uchi villager, its all subjective really. That being said, Deirdre is the best uchi hands down and I will fight anyone who states otherwise to the death.
KATT. Always Katt.
Pashmina is a super lovely choice!
Fuchsia and Tammy are also my favourites when it comes to more colourful villagers.
And Muffy is cute too!
I'd definitely say phoebe. Imo the uchi is one of if not the weakest personality in the game in terms of villagers to choose from so I think it's a no brainer for phoebe.
Had Phoebe, but she left due to a TT'ing incident.
Had Hazel, but had to let her go since I needed a slot (But I really liked Hazel </3)
And just gave Frita away to someone.