Video Conference/Chat

Tandem to FHIR REST(dueling projects prevent my tunnel vision) i’m looking into Video Chat/Conference and hoping for feedback.
My initial thought is to add to Portal Chat where selective private text chat can also occur within the video conference. Chat is available both in Portal and OpenEMR with perhaps tying to appointments and encounters.(Billing) Not sure how this would be billed but I assume duration needs to be recorded as well as maybe a custom encounter form.
The conference itself is a question, for instance; do I set up a conference room for patient/providers to join at scheduled times or leave it to the user to include conferees at conference time? It’s unclear to me if one to one would be the dominate use case or really what the work flow should be.

I guess what i’m asking is what would the dominant use case scenario and disciplines be for an initial offering?