Lighter boats are easier to handle?? On the beach yes, but on the water I don't agree with you at all.
From experience I would say the heavier boats are less flighty, more forgiving and easier to drive.
But Hell... what do I know?
I agree. Moving from the 5.2 (big, heavy, really heavy) to the Stealth (probably half the weight, or close to it) the difference on the water is huge:
In light wind it is actually easier to sail the 5.2. Once it gets some speed it will not stop. In stealth you move your but 50cms one way or another and that's enough to stop the boat dead...
In high wind you better be quick on the Stealth when a gust hits. On the 5.2 you have time to sheet out or go on the trapeze. On the Stealth if you are not quick enough, you're in for a bath.