As for the designs in the Arkham games, I'd like to assume only the folks who've played the games will "get" it. When I first saw the designs in 2008, I hated them. Playing the games, it makes a lot of sense because here we have a Batman who's pushed to his physical limits in the span of just one night in each games. It feels more "believable" that a guy this big would survive 12 hours of non-stop punching, flipping, and ridiculous physical exertion without his muscles turning into a puddle of goo the next day.
Honestly, I like most of the game designs. I think, though, if I had to do a bottom 5, I'd probably go:
1. Bane (Asylum/City; though I loathe Arkham Origins, on a matter of principle, based on my own experiences with that game, credit where it's due: their Bane beat the hell out of the pinheaded idiot from Asylum and City, in terms of both characterization and design)
2. Croc (Asylum/City; while I don't particularly care for his full blown naked Alligator look in AK, either, I always thought those teeth looked ridiculous and gave him an almost overly cartoony look that took you out of it)
3. Harley Quinn (Arkham City; personally, I've always despised Arkham City's murderous biker Harley. I think, in terms of characterization, I've always liked Harley to be, not necessarily innocent, but redeemable; there when the Joker does his horrible ****, but never really crossing that line, herself; she's a victim as much as anybody else, but, if stripping her of that wasn't enough, the terrible, generic biker look pushed it over the edge; outside of a few Jokercentric tattoos, she may as well have been any background stripper from an episode of Sons of Anarchy; it was bland, uninspired, and just plain terrible)
4. Zsasz (that combination of the weird prison bicycle shorts, along with the padlocked Joker and the giant forehead slashes; ewww)
5. The Scarecrow (Arkham Asylum; I actually remember everyone kind of liking this design, initially, though I'd argue that they liked the badass moments he starred in, and, thusly, were more forgiving of what I can only describe as the star of a Clive Parker penned Indie comic about the lost member of a heavy metal screamo band)
Dishonorable mention: The Riddler(City/Knight; take a shower, or are you too intelligent to see that you're ****ing gross, dude? If anyone was wondering what Matthew Lesko would look like homeless and living in the bathroom of a Costco, here's your answer. )