@wesleyote with most health insurance providers if you can prove cohabitation and interdependence they will extend health insurance to your friend. Just say "live-in partner" and "what forms of documentation do I need to extend coverage to my domestic partner?" when calling and they should tell you what you need.

it's a massive pain in the ass because you have to re-attest every time the policy changes but if half a polycule has health insurance you can get the whole group covered this way. Buddy up on who has insurance relationship and it's easier to keep it consistent year to year, switching it up on a rotation invites questions.

Only time I would recommend rotating is if someone has a very expensive chronic illness, every time plans are renewed review all the coverages and premiums and rotate that member to the best plan for coverage:cost ratio

You can also dual-coverage and have a primary and secondary insurance, so after the primary insurance is billed you can send the patient bill to the secondary insurance to shave a bit more off the out-of-pocket. Only worth it if you/re polycule has a lot of health needs but could be useful.