What I noticed particularly in "Some Like It Red" is that they completely eschew the walking-in-heels jokes. Partly this is obviously Fraser's omnicompetence at work, but partly I think it's because they don't think drag is funny in and of itself. As you say, Ms. Fraser isn't played for laughs; the humor is all about how others react to her: the fact that neither Welsh nor Ray recognize Fraser as Fraser, NOR recognize him as a man in drag, even though those shoulders are a dead giveaway. Partly, yes, that's maintaining the illusion that Paul Gross can pass as a woman, but partly it's making a perfectly serious point about what people actually notice and how much of it is based on superficial markers.

And, yes, they totally do the role-reversal thing, with Fraser getting sexually harassed, hit on, and generally objectified by every woman who sees him. (There's a country that knows what to export.) And although they never make an overt point of it, the fact that Fraser doesn't "ask for it" and has no recourse to make them stop ... is pretty much what sexual harassment is all about.