> Yes, there are far better alternatives out there, so if we could stop using skype and switch to something else, would be a great move here.

What? There are secure text-only clients, but voice/video/group video? Where is the more secure version of those? Or is this going to go down the road of "set up your own VoIP service" again?

People always say there are tons of alternatives to Skype... Where are these alternatives and why aren't they popular?

There is Tox, Jitsi, Firefox Hello and other services based on Webrtc.

Signal has a secure calling option but it isn't very robust and I've had issues with it.

Indeed I originally used it because it was cross platform, buy in meant relatives are now trained and comfortable with it. Personally I like HTTPS://appear.in for voice chat but one needs the phonebook, voicemail, online-indicator and such parts for it all to work efficiently.