Interesting thread. But how can we really place ourselves on a scale unless we've experienced a wide range of situations?
At the moment I'm mono. Z and I have a passionate relationship that is only a couple of years old (he is poly). We have briefly tried a triad which didn't work for either of us but in hindsight was probably a bit of a stretch for me as I was only bi-curious. In the time I've been with Z I have had no attraction for anyone else.
BUT, in my previous marriage I had a few affairs while still loving (or believing that I still loved) my husband. The last one galvanized things for me; I decided that I was sick of the dishonesty and put it to hubby that we should have an open marriage (hadn't heard of polyamory). He declined.
If a special someone dropped into my life who knows what could happen. But until it happens, or in the absence of it happening after many years I couldn't really say where I'd fall except that I'm obviously not at either end of the scale. Maybe slap-bang in the middle?
Nice to see more poms on the board.