I have been thinking about my own question since having posted it. I guess I really want to know what solo poly people fantasize about being the kinds of relationship situations/structures they want. Basically, I feel at this point in my life as I head into being a divorced person on my own, I don't want to jump into another cohabitation setup again. Not saying I won't ever, but I don't see it happening for a long while. My ideal situation would be to remain independent, living on my own, and to have two to four long-term boyfriends whom I see at varying frequency depending on how involved/invested we are. Like maybe one of them would be someone I see very infrequently for romantic trips or something, and others would be more involved and familiar with my day-to-day life. I know this may seem selfish, but I like the idea of one of them being totally mono with me. In my fantasy, I don't feel it necessary for all of them to meet and get along, but if they did, that would be nice. I would want to be up front and honest with all of them, so that we all know what's going on and we all play safe.
A long time ago, in the early 1980s, when I moved into my first NYC apartment, a handyman working on my kitchen said to me, "Oh, a young girl like you's gotta get a few different boyfriends - one's a doctor, one's a dentist, one's a plumber, one's a carpenter, so you get everything done." It made me laugh back then, but if I think about the different sides of who I am, I would want a boyfriend that gets along with each, one intellectual, one creative, one down-to-earth, one geeky.
It's all just a fantasy, anyway.