What I was thinking would be based on the upper limit of the actual competitive field, up to say, some average arbitrary weight. This arbitrary weight would be subject to the National Class description (the MNA) for the geographical group, but would be revised to reflect the field for international events. That said, I understand what you are saying in that a team from Malaysia might have to carry 100 lbs if sailing against a Western team. Not impossible, but definitely an equalizer for potentially unhealthy weight behaviors, or skewed crew selections.

It's only an idea, but given the competiveness of the lighter crews in light conditions, such handicapping would attract and help to maintain interest of both younger and older participants, and mixed teams to the the sanctioned events. The local rules could conceivably be fudged to allow substitutions of crews of different weights to maximize participation on weekend 'fun' events while maintaining the weight parity.

Weight 'classes' is a non-starter for sailing, I'd say.