I actually think the OP has a rather good idea -- not a Co-Op, but rather a group (health) insurance. A group insurance for cruisers -- not just CF, but any full-time cruiser who desired to join and met the criteria. This is a large group of people and smaller groups are insured all the time at considerable discounts.
Moreover, I just met an individual who is employed by a large group (US Restaurant Chain) and his company just switched to a format where the premiums are no longer taken from his paycheck, but he has to pay it by draft
from his checking account. So, the payment format could be the same.
I think the bigger questions are:
1. How many cruisers are now otherwise insured with a good plan (i.e., from former employer) and don't have a need for this product?
2. How many cruisers are completely uninsured for healthcare and need at least a catastropic (major medical) plan?
We must have a CF member
who is in the insurance business who can speak to this. And, no, I am not in the insurance business -- I am in healthcare.