Coming at this as a straight, monogamous person the difference for me is how they're perceived and presented by mainstream culture, not the difference of how they're experienced from the inside. The fact I think of it this way is probably another thing I need to work on.

I grew up being aware that some people "Were just born" with attractions to the same gender, or "in the wrong body"(*), I don't remember ever not being actively against homophobia and transphobia as I perceived them. (Although I didn't think of them as related until I was a lot older)

But it's only when I got to uni that I encountered the idea of polyamory etc as legitimate lifestyles and sexualities rather than unhealthy deviance, brief experimentation, or philosophic/religious etc choice. I'm still at a much earlier stage of gaining understanding on these issues so I tend to think of them separately. I have a feeling if I wrote a post about it I'd just embarrass myself :/

I've been meaning to go on more of a learning-about-queer-theory self education journey like I have been with racism, I have a LOT of not-heteronormative friends who might appreciate me being less clueless without having to educate me themselves.

(*)These being my simplistic child-of-the-80s understandings