One of the benefits to running a bridge rather than a regular relay is that unlike running a regular relay, running a bridge only benefits the good actors. All that a bridge does is hides from your local network the fact that you're using Tor, so bad actors have nothing to gain by using bridges rather than just connecting to Tor normally.
Running a bridge requires exposing a port right? If so, couldn't that impact his IP's reputation, assuming he has static?
What reputation systems ding you for listening on a port? It's not an open proxy/relay or anything like that.