Here is my tier list. I like most smug villagers and I will give an explanation for each tier:
S- Eugene is my smug dream villager; I like how cool he looks. Hans is the best gorilla, and I like his yeti basis. Henry, Kyle, Lopez, Tex, and Zell all resemble real-life animals (an American bullfrog, an African wild dog, a Thomson's gazelle, and African penguin, and a blackbuck or oryx respectively) which helps them stand out, which I love. Jacques is my favorite bird villager, and I like his beanie and French-based origin. Ken is a cool ninja chicken, and I like how his name can involve his species. Lucha is a wrestler/luchador, and he reminds me of Hawlucha, one of my favorite Pokemon. And finally, O'Hare is excellent. I picture him as an Irish bunny tourist, with his stereotypical tourist shirt and reddish-orange tuft of hair on his head.
A- Chadder is a good example of the smug personality, with his tuxedo. I also like his cheese theme, though to me, he look a little mischievous. Colton is a good-looking horse and I like his house interior. Curlos is underrated, and I like his name pun, which suits him. Graham is adorable; I like his glasses and he was the first hamster that I got to know of. Julian stands out because he resembles a unicorn, though I find his eyes a bit problematic. Keaton is colorful and unique (to me he resembles a blue and yellow macaw). Kidd is cool-looking, Lionel is a good lion that looks like a wise gentleman, Marshal is cute and a parody video helped me like him (he's extremely popular, which makes me a bit biased towards. In addition, I think there are better squirrels in my opinion.), Olaf is interesting and I found him on a mystery island, and though he seems to be a knockoff (he looks like a matador to me), I like how he has legwear, Phil resembles a pheasant, which makes him stand out, though he's an ostrich, which have a different morphology than pheasants, Pietro is colorful and funny-looking, though he can creepy to others, Quillson is underrated and I really like how he stands out (he looks a bit ugly, but in a good way), Raymond is a cool business cat that I'd like more if he weren't extremely popular, and I like Shep's basis, though I do wish that I could see what his eyes look like.
B- Both Huck and Leopold are fine in my opinion. Huck looks a bit strange and I wish Leopold never had the jock personality (I think there need to be more non-jock lions), but I will appreciate both of them for being smug villagers that appeared before New Leaf (the game that introduced the personality).
C- Beardo is a lit problematic, but I will appreciate him for having his species in his name and resembling a gentleman, Ed's eyes are problematic, and before becoming smug, he was a jock which I do not think made any sense for him (lazy would have been a better placeholder personality), and Hippeux is strange. He has hair on his head that I don't think makes him good, and his skin color doesn't help him. Also, the fact that his real name isn't that but something else (Gary is his real name, this is confirmed in PC) makes him almost bad enough for me to dislike. The good things about him are that the name he goes by has an "x" in it, the fact that he both has an uncommon personality and an uncommon species, and that he is currently the only hippo to be introduced after the Japanese-exclusive Dobutsu no Mori e+. In short, he almost made it to D tier, which consist of the villagers I dislike.
D- Chops is arrogant and ugly. I was forced to have him on my island and it took me so long to kick him out. Klaus I wouldn't have disliked if not for how creepy he may be. Though his origin is a good one, his permanent angry/depressed face doesn't help him at all. And Rodney is a short and ugly mess. The tuft of pink hair on him contrasts greatly with his blue fur, his tired eyes don't look great, and he doesn't look gentleman-like at all aside from his catchphrase. He is easily the worst smug villager and one of, if not, the worst villagers ever created.