Though not technically part of the drive train, why not pick up some SPD-SL pedals and some sidi's or Shimano Carbon soled shoes and replace the pedals on your road and FG? Egg beaters are fine for walkable shoes, but some nice stiff shoes and SPD-SL's will probably get you more power to the ground. Probably will do more than drivetrain enhancements. I run SPD-SL's on my roadie and love them. I want to walk on my SS so have SPD style cleats.