I don’t think there’s a Bad Map in the game, and don’t really think there ever was - including old Ice, but CORSAT is a bit of a stretch.
I notably am a highly fluid player. I play Engineering, Medical, rank-and-file or Command pretty interchangeably but with a different character designed for each. I also tend to shake-up my loadout for each map, because the maps are clearly meant to be approached in different ways.
Fiorna’s, Varadeo, and Chance’s are great, until you get a batch of Marines or Xenos who didn’t think to bring anti-wall measures to clear a path around Go Fuck Yourself Alley, whose atmosphere is 50% boiler gas and 30% bullet at any given time.
LV and Solaris are classics though not my personal cup of tea, but people unwilling to shore-up backlines and a strong defense of the center of the map are liable to result in 3-hour rounds when one side loses its siege, has to fall back past Hydro (LV) or Admin (BR), and all the way back home to lick their wounds enough to keep poking at the other’s defenses after a crushing retreat. Kutjevo - LV/Solaris except better - suffers similiarly some rounds.
Finally, some more complex maps like Trijent, Shiva’s Snowball and Ice (Goddess rest their weary souls), or Sorokyne offer excellent opportunities to switch things up. Making lanes in snow to funnel Xenomorphs/Marines for risk of slowdown, marines utilizing elevators/trams to transport dozens of marines in seconds, and the Xenomorph’s ability to attack from a large variety of angles due to all the open ground for tunneling.
The issue is, ultimately, that means adapting. You’d have to join the round, absorb which map you’re playing on, and strategize beyond rushing from A to B and bunkering down in some place a dedicated commtech or two worked hard to build. If you flounder in a Kutjevo siege then you ultimately don’t have too far to run to get back to home base, but taking the same “no fortified fall-back point” means an absolute slaughter on Trijent, Fiorna, or Varadeo, which translates to a lot of people having poor views of less simplistic maps.