1 and 2 are pretty widely known, and will appear in many commentaries. Mostly. Not including things like connection of Lev 18:22 with pagan temples.
However most scholars that I've read, even affirming ones, would not agree with 3, and regard ansenokoitai as a conjecture, but a likely one. They would not agree with the post's concept of nature. While Paul doesn't give details, his near contemporary, Philo, is clear that same-gender sex is against nature, with nature being a kind of ambiguous term meaning partly God's intention and occurrence in nature. As part of the argument he cites the (incorrect) fact that animals don't do same-gender sex. While this isn't true, it clarifies his idea of nature as something more general than the specific individual. See 1 Cor 11:14 for another exampe of Paul's use of nature. Also dubious by our understanding, but still clearly a general concept and not an individual's specific nature.
Aside from people who I would call advocates (i.e. people who don't otherwise appear as scholars), pretty much everyone thinks Paul accepts the then-current Jewish condemnation of same-gender sex. That they also didn't accept the idea that some people were only attracted to same-gender sex is one possible explanation (Philo specifically denies that sexual orientation exists), as is the association with these ideas with stereotyped masculinity. But there's little question that Paul would have accepted the widespread rejection of same-gender sex, and would not have imagined exceptions.
I would cite Bill Loader's book "Sex: Then and Now." He's done work in Jewish attitudes towards sex. That book draws on his research but has a more popular tone.