I would remove the Minirazor, and bring back the old torpedo system, with normal speed not the current one, the launch is delayed and makes it completely useless. Also add an emp torpedo into game to replace the inferno.
Players who use a weapon with a high damage per second should have a chance to kill or at least damage themselfs with it, like with the current missles/mines. If you get a cd in the face....Boom!
Also decrease the cruise distruptor's explosion range. Could keep the cd+mine trick but it would be a lot harder.