I quite like the high ponytail, female hairstyle number 7 on that image, because I have and prefer long hair and that's the closest I feel we get to it in the game. I would love to see more long hairstyles introduced.
I also like the female hairstyles number 1, 15, and 16, although I wish the tiny pigtails on number 16 could be seen from the front.
I don't really have a favorite male hairstyle as I generally play as female characters, but my one male alt has the last male hairstyle. I liked it for him because it was kind of shaggy and suited his image.
I like female hairs 4, 9, 14 and 16, and male hairs 4, 13, and 16. My female mayor has had all of these hairstyles at some point because I have had all of these hairstyles at some point, lol.
It really depends on the hair color for me, but generally I like Girl Hairstyles 10, 12, 13 & 14. I really wish there were more wavy/curly hairstyles, though! For Boy Hairstyles, I haven't had too many boy characters, but I think I like 4, 13, 14 & 16.
The grin and bear it hairstyle is my current favorite. It's the only hairstyle that's long and doesn't have bangs. (Currently trying to grow mine out and it's being a pain.) I also like the fight and overcome one, but I wish the hair was longer.
The Bun, I hope the next game has longer hair/more varity, maybe choosing front (bangs) and back (ponytail, bun, I'm personally hoping for a hoping for a long braid or a messy knot which is how I do my hair)
Right now, I have the female "Extremely formal - Business! Fresh!" hair type, but I also have had the "Extremely Formal - Private! - It's a date!" hair type (if that is the one with the bangs & pig tails). I think I'll switch to this hair style again today actually! I love to change now & then
In terms of colour, I used to have pink hair, but I thought it didn't go well with the Flower Fairy Wig when I finally obtained that one (not enough contrast with the bow), so then I switched to purple.
Right now I love wearing the Celeste bow the most I think. It's so pretty
I've had the ponytail (the 7th female hairstyle) a lot recently, and it's definitely a favorite of mine. I like the bangs.
I also like the 16th male one quite a lot, it's cute.