I am disturbed that no one other than myself is concerned about light weight pilots flying with lead filled cockpits.

Probably because most pilots have the opposite problem .

I myself have the same problem as you have. When I had a club class
glider I created a seat pan mold and then used lead pellets with epoxy
to fill it. I also put belts through it and attached them to the seat
belt mount points. The extra weight was 55 lb. By the way I still have
it if anyone is interested. It is made for SZD-55-1. Yes it was a lot
of work but much less work than gaining 55 lb and much healthier .
Would I do it again? No, I make too many mistakes to blame them on
weight.

For the pilots at the top of the ladder they might have a different
view.