1. Retreating blade stall begins at the tip of the retreating blade due to two factors - downflap and reduced blade velocity. If you shorten the blade, you shorten downflap and also reduce blade velocity causing a corresponding large reduction in lift so you must increase rotational velocity of the blade to compensate. Of course, you will eventually get to a point where you've increased rotational velocity so much that you run into compressibility (supersonic flow) on the advancing blade. The record breaking Westland Lynx walked a fine line between retreating blade stall and advancing blade compressibility, and that's why it's the realm of test pilots and engineers. Screw up your temperature or pressure calculations just a little bit and you've lost your rotor system.
2. I'd say definitely, yes. High wing (or disc) loading = smoother ride. I actually had some first time helo passengers mention this just today. They were expecting the helicopter to be bumpy and the smoothness surprised them. The exception, of course, is at high speed because a heavy helo gets into retreating blade stall earlier, and therefore the vibration levels for a heavy helo are higher at speeds close to Vne than those for a light helo.