1. Cranky (by miles)
2. Uchi
3. Peppy
4. Jock
5. Smug
6. Snooty
7. Normal
8. Lazy
Big switch from the last times I played the games. Those aren't my favourite personalities, but that's how I feel, based on dialogue in ACNH. I do feel some personalities have changed over the years!
I think Cranky are the most consistently interesting to talk to, and quite relatable and funny. Getting to know Kabuki has been very rewarding. They're not that grumpy any more, but they've always had that gruff exterior/heart of gold thing.
Uchi, Peppy, and Jock are generally fun for me to chat to. I can see why people say Jocks are a bit one-dimensional, but it doesn't really bother me. It's just their thing, and they have more to their personality than muscles. (I'm probably more tolerant of that gimmick because I know people like that well.) They're confident, friendly, a bit foolish, generally caring, etc. Peppies are their same old selves but updated for the 2010s (although you can definitely see they're meant to be corny).
Smugs are fine, they're just not my cup of tea. I've always loved the Snooty type, and now they're so mild! But I don't mind them. Also, all of these personality types have AMAZING conversations with other villagers.
The Normal and Lazy personalities are a bit boring, imo. The Lazy personality has way too many actively off-putting lines. Like, if the Jocks are gross talking about sweat, so are the Lazy personalities - they both need help with their personal grooming, I think. I think the bug friend thing is pushed way too far at the expense of the general personality trait (like, rather than them seeming overly whimsical and daydreamy, they just seem REALLY HUNG UP ON BUGS? But I like the lines where it's like 'oh I fell in the river and met some fish' or whatever), and I probably take it a bit personally because they used to be my favourites after the Peppies.
The Normal personalities are sweet and shy, but often a bit too boring. AC needs to be a little out there to really hit, imo. Not mean, just... larger than life? Think Moppina from Wild World.

As a footnote, I think the Lazy conversations with other villagers are generally better than the Normal ones, but I see those less often than I talk to my Lazy villager one on one, y'know?
All these are just my personal feelings. I have beloved villagers from each type!