A couple of points.
1) Shimano road hydrualics greatly benefit from using MTB lines. Shimano, in their infinite wisdom, decided road riders weren't ready for MTB style braking feel, and intentionally used more flexible brake lines. The result is the lever feel is less firm that if you swap to the newer MTB lines.
2) Hydraulics allow for a dramatic reduction in lever travel and force. If you a 170 lbs man, caliper brakes are fine, but for riders with small hands (especially women) will benefit from the reduced lever travel and pull force required. With caliper brakes, women are frequently forced to choose between inadequate pad clearances or levers that are too far forward.