I tried searching for previous threads asking for this (surely they must exist), but the search is dysfunctional now and only returns an error message.

Anyway, my feature request is to add a checkbox in LimeWire's options, next to the words: Allow other users to browse my shared files.

That is, make sharing the list of your shared files optional.

Lots of people disagree with me about this, but more people agree, and it should really be up to each user.

This would neither encourage nor discourage leeching. If you think it would, you haven't thought about it enough.