Even the 2104 is way to soft, it you want to launch or shift hard at all you will want a rear engine mount, I like the Cobb for control and less harshness than some being offered but more came out since I got mine so make sure to review them.
Softer suspension bushings would soften the harshness of the ride a bit but also likely to reduce overall handling and feedback. Stiffer bushings to load up when twisted more than softer ones, all such bushings stiffen the movement of the related pivot points thus alter handing characteristics. That is why I changed to all urethane with inserts to eliminate that issue and the car is no more and perhaps even less harsh in vibration, shock, etc, than stock and rides better with the added help of the "race" version of the BC coilovers.