In Washington, the two largest health insurance companies have just stopped writing individual medical policies. The only way you can get health insurance from them is through an employer plan. This may be a competitive advantage . . . My suggestion is that your contribution to the premiums be based on the number of hours that people work. I feel that the contribution has to be calculated on the same basis for everyone or we are penalizing the single workers because they chose not to get married.
Hours is the safest way to go.
Let me know if you want to explore this in more detail.