On the subject of the cable company serving as home telephone provider: in Lawrence we have a local cable company that does a "very" poor job with this and most people want to change back after they've changed!
I had the cable VOIP and switched to
Voicepulse years ago.
I only use the cable for modem, my TV is on satellite.
Voicepulse works fine for me, we use it as an outgoing line and fax line, for $25 bucks a month.
It has a great webpage account control panel, you can do whatever you need, filters, blocks, hide your ID +++ and time stamp billing.
If you have someone that calls often, like family, you can set up a number in their area code for $5 bucks a month and they call a local number so they are not charged long distance rates. I know...long distance is becoming a thing of the past, but many folks are still using the regular old "twisted pair" and pay extra for long distance calls. For our clients that don't use the internet we setup a local number in their area, it works great!