Your VOIP does seem a bit cumbersome, my phone just plugged in the back of the router in a dedicated phone socket and away it went.My VoIP, has still to be tested, on an outgoing call. I've rung it, from my mobile, to confirm it works. I then had Avril ring it simultaneously, and then we discovered it had call waiting. I know it must have other VoIP features, but I have little idea what. YouFibre don't give any clues at all about the service.
As for phone use i did have unlimited calls for may years as I was able to negotiate a good deal so it was basically free but this time they stood fast, I did some thinking and I hardly ever use the phone now as its all mobile and more often than not either WhatsApp or video WhatsApp calls.