As you just touched on the variety, in my case there has been the couple who opened up to a third and moved every relationship to the same level kind of immediately. And moved the new person in as well. This worked great for us, even though the men aren't sexually involved with each other. You can have what you dream of, it may just take unexpected bumps in the road to get there. So be open for whatever comes your way
Good luck and welcome.
Facts: 30, female, bi, v-type relationship with Sward (husband, straight, mono) and Lin (boyfriend, straight, mono), poly-fi and co-primary.