I would contact GC and discuss softer springs with them. You can pick your spring spec based on your needs. Plus you can adjust the ride height to add more suspension travel for more comfort. Far better option than going to H & R springs.
'04 E46 M3 - Jet Black - Sold
'08 E90 M3 - Alpine White - Sold
'13 E92 M3 - Silverstone II - Sold
'13 E92 M3 - Alpine White - Ohlins TTX, AP Racing BBK, Cobra Seats, Akrapovic GT4, BBS E88, Volk TE37, OE GTS - Aero, 1/2 Cage & Seat Delete