Ever since Red Death got added to the game, and perhaps even before, Crimson has been completely outclassed. Red Death does basically the same thing as Crimson but massively better, to the point where you can barely even compare them. Even heal clip weapons are better at this point, because they heal for more, and can have a second perk. Outside of being decent with Lucky Pants, Crimson just seems completely useless now. It needs some pretty serious buffs if it's ever going to have a place in the game.