That is a very important aspect, and the developers of the Avast Firewall better keep this in mind. You have to consider various patterns of users, and have various levels of the firewall with these various users in mind.
I for instance am a user that like my port 80 actions safe/secure, and also my media ports (radio, video etc). I like secure webmail. I do not use services like messaging, skype etc. I like to monitor what goes on under the hood. Other users have other demands: safe downloading, sharing, blogging, Web 2.0 or Web 3.0 security. Not an easy task to serve a firewall for all tastes...
polonus