How about residential being allowed outgoing FAX(from files) as a standard feature?

Perhaps allow 3 free calls per month, with a small fee for more?

Your a-la-cart incoming FAX number is still great for the opposite direction. Combined with residential, that could bump the free outgoing quota.

Outgoing FAX would just offer a security blanket that may hook some people on the whole FAX service, and others may never use. And it would define VOIPo as being different in another good way.