Great game, but crappy support.
For one, the game doesn't have the best community. It can take forever to get into a match. And once you do, the game doesn't do that great of a job balancing the two team. There are time when I'm on a team of people with a level of less than 30, while half of the other team is over 100.
Another problem is the support from the developers. At first, it was great! We got free DLC with a new map, game mode, and weapons. Even after that, the paid DLC was decent. But after a while, the DLC just stopped. This gave me no reason to keep playing. Like I said, once you get playing, the game is highly addictive, but I rarely do play, and when I do, almost no one else is. At the moment, we only have 7 maps, which got old, and 4 game-modes, and they also got old. It's sad, because the game has so much potential for game-modes and maps. Not to mention the fact that it's based on Batman.
In fact, that's another problem with the game. Despite being based in the Batman universe, it has next to nothing to do with Batman. The two teams might as well be called heroes and villains, there are only two guns/gadgets that even reference Batman, and the only three maps that are actual Gotham landmarks barely reference Batman at all. Crime Alley looks nothing like the comics, and doesn't have chalk outlines of Thomas and Martha Wayne, which should have been obvious. The Arkham Asylum map doesn't have references to Batman villains, doesn't look any thing like an Asylum, and, if I hadn't been told, I would have never guessed it was supposed to be Arkham. The most accurate map is Amusement Miles, and even that looks nothing like an amusement park.
It's a shame, considering the missed potential considering the source material. We could have had gadgets like Catwoman's whip, Joker gas, Bane's venom, Penguin's umbrella, Scarecrow's fear gas, Mad hatter's hat Nightwing's escrima sticks, Robin's staff, and more. In terms of maps, we could have had Wayne manor, the police station, Blackgate prison, Poison Ivy's greenhouse, Joker's abandoned warehouse, Penguin's aviary, Scarecrow's haunted house, Mr. Freeze's...ice...place, and, not to mention, THE BATCAVE! Yeah, it seems like a no-brainer, the the Batcave isn't a map.
As you can see, Gotham City Impostors isn't a perfect game. It has tons of problems. But despite everything, it's still fun. In fact, that's it's biggest crime. It's so fun, and has so much potential, it's a disappointment it doesn't live up to it. Still, at least it has that potential, and, when I get into a game, and look at the game as it is, as it should be, the game is extremely fun.