I'm in the middle of estate planning myself. Or more accurately trying to avoid it.
Where collections (not just pins) end up is turning into a big problem. No one
in the family has much interest and the volume would be overwhelming for
any one (or 10) people.

On one hand, want to keep and enjoy the things I've collected and restored
in my lifetime but on the other hand don't want to see the majority end
up in the landfill or sold off by crooked 'estate liquidators' after I croak. There is a
special place in hell for these scum bags.

One possibility is donate collections to museums. In fact I've done that with
a few really nice items (not pins) only to see them sold off. So thats not
a great option either.

Don't have any good answers yet.
Steve