Quick note about homosexuality in ancient Rome: Roman Men who were possessed of the rights to Libertas and rulership over Familia were
never permitted to be the lower half. It was socially unacceptable, period, because Roman men were expected to be the pinnacle of dominance. They could only take upon themselves those in the Infamia classes (slaves, prostitutes, entertainers, et cetera) who (with the exception of slaves obviously), while technically "free" by Roman laws, were second class citizens that often did not own property and had no legal say over their families. Thus, middle and upper class Roman men could boink lower class Roman men as the doms, and the Infamia had nothing to really
lose in such a relationship, as they were already on the bottom rungs of society.
Basically, male on male wasn't just about the sex itself with dom vs sub, it was also entirely about social class. If an upper class male boinks a lower class male, neither person loses anything: The former retains their "Roman qualities" and the latter had nothing to lose to begin with. Under no other circumstances was this behaviour condoned or permitted, it was often compared to the Greeks, and used to dehumanize and make them inferior to the superior Roman culture.
In terms of Roman women boinking other women, early antiquity there wasn't much about it aside from "this is freakish." Later on during the late Republic era onward, they started to write about it more (or at least there are more surviving records), but they could only imagine such a relationship if one of the women in the pairing was "possessed of phallic vigor." IE: They possessed a dildo, or an especially enlarged clitoris, with which to use as a pseudo-penis. Yeah, they were as imaginative and weird as the Japanese are today.
As for everything else, completely agree. I just wanted to clarify the whole "Roman men boinking other men" thing, because it was more the Greeks that did the whole pedophilia thing. More specifically, the Spartan lifestyle of Agoge pretty much included it as core, because somehow, male, uhh... "Liquids", had magical properties by which to confer additional manliness to the, uh, younger receivers.
... It's fucking weird, okay? But in like, a completely delightful and obscene way.