hi davery--If I remember correctly, you've already set up the firewall and router, and are sharing a good number of files. Here are a few more tips--sorry if you already know of these.

-test connections by searching and downloading a fairly common file every once in a while. "Serial Box" is widely shared by OSX machines, and usually gives >50 hits quite quickly.

-check with your ISP. They may be experimenting with file sharing controls, or slowing tranfers while screening for viruses, for example.

- keep an eye on the View-> Connections pane. If your connections give poor results, disconnect and reconnect to new hosts.

-Find the best times to search. You can get more info on patterns in the Gnutella Netsize here