I was pleased to see a brief reference to Mayweather experimenting romantically as a youngster with someone named "Juan," who is presumably male. Of course, many people "experiment" with same-sex relationships early in life and then later on settle into identifying as heterosexual, so we shouldn't read too much into this reference, vis à vis Mayweather's sexual orientation/preferences as an adult. But it's still a nice acknowledging touch of diversity on
Christopher's part.
I'm trying to decide if
Christopher is the first to do this (take a presumed-straight male character from canon and acknowledge non-heterosexual encounters in the past). Andrew J. Robinson (and to a lesser extent,
Una McCormack) have done this with Garak, but there was on-screen precedent to suggest that.
Of course, there was all that Kirk/Spock slashy business way back when, but that was a little different.
Ah! Michael A. Martin established
Admiral Krell as having a husband in one of the Romulan War books. It's a little bit of a cheat, because we really had no reason to presume either way about Krell's sexuality from his onscreen appearances, but still.
Others that I've forgotten?