I'm not sure that the feedback is particularly helpful here. I have the same gripe in a way and rightly or wrongly see it as follows:

My understanding is that Browse Host means that people can look at the "room in your house" that you've agreed to let people share already. But if you can't browse that room then surely they can't be sharing.

I'm prepared to accept that its a sporadic state and that people who are sometimes not open maybe at other times; so filtering them may not be the best solution.

What I'd like would be preference given to people who are available. At the moment, when I can be bothered, I kill the upload of people who's host I can't browse in favour of queued people whose files are available. An automatic way of doing this seems like a good idea to me.

One final thought - A large amount of people who I can browse have little or nothing in their "room" - maybe they're the real freeloaders who you should be filtering.