Should get rid of scarisland and keep dm_island, that's the best one IMO.
Scar Island is the one that we all spawn on the beach and the underground area has that toxic shit yes? Because while I like both island maps, that's the one I prefer least, for the toxic shit and the fact that when I die my spectator always spawns in that box in the sky, and I hate having to do work to get back to viewing the others.
I personally love haunts and kinda like concentration. I have only seen haunts either keep people in or bring people in, I have never once seen it kill the server.
"Options are good. Keeps people choosing." -Craig Benzine (Wheezy waiter) 2010
I'm not a huge fan of scarisland myself, however I wouldn't like Concentration or Haunts removed as I've never seen anyone have a problem with those maps nor have I seen them kill the server population.