Hmm, while I can find a charm in each and every animal (my favorites being reptiles, many small mammals, ratites and penguins), some I find... Kinda dull.
- Meerkats. Removing my bias, I find them very entertaining. But guess what? I think of that of ALL mongooses. And while banded and yellow and dwarf mongooses are still obscure to the public eye, meerkats are eeeeeeverywhere... And sooo overrated too! So yeah, meerkats are the most famous mongooses, but I feel that they're overrated.
Plus banded mongooses smell nicer.
- Wildebeest: Yeah, I don't know why, but... Wildebeest don't appeal to me that much, to be quite honest. I rarely see them doo much, and they're kind of a vanilla animal to me. Waaay too many of them in pop culture. I prefer to look at any other type of antelope (Sitatunga are my favorites).
- White tigers, ligers, etc.: While I love big cats, I have an ambivalous relationship to seeing them in zoos. Most of the time, I see them lounging around, on the far end of a moat, which doesn't appeal to me much... But seeing them up-close with a glass window or a chain link fence between us is very engrossing.

I prefer smaller cats though. Clouded leopards are my BAE.
Buuut in any case, I'm not a fan of zoos displaying white tigers, ligers, and any other unnaturally bred mutant feline. It just comes off as a ploy to get people to visit the zoo. I mean, sometimes they rescue circus animals, and that's fine, but normally I feel that they really overhype these frankly unnatural animals...
- Red kangaroo. Yeah, I love wallabies, pademelons, bettongs... But red kangaroos are surprisingly lazy! Like, hoooly hell, most of the time I see them, they're all lying down idly in the shade. I mean, sure, I'd do that too if food was assured for me every day. Buuuut yeah, I prefer their smaller cousins. I love walking among them in walk-through enclosures. :3
- Waterfowl. Kind of an honorable mention. When I go to new zoos, I take my time to observe them and appreciate them. But at my local Barcelona zoo, I can't be bothered to pay them too much attention, to be honest. Except for flamingos, screamers and penguins, of course.
- Brown bears: another honorable mention. I just see them in every zoo I visit, and I'm quite frankly bored to tears by them at this point... I prefer any other type of bear than them. I find them so plain, to be honest. I mean, awesome animal objectively, but it's the meerkat effect; I see waaaay too many of these guys.