Great points. I certainly can't speak definitively but I gather some people think that Epicurus was frequently talking about "sages" in the sense of dedicated lifelong philosophers. There's a book out there "Epicurus The Sage" and i have never liked that title or term. I personally don't think Epicurus applied his teachings only to a very small category of super-high-achieving people.
it sounds to me like this notion that the sage is some superhuman specimen has some Stoic connections. In recent reading of On Ends for the podcast, I've come across the contention that Chrysippus held wise men/sages to be as rare as a phoenix, which presumably means extremely rare.
I think Epicurus was describing a philosophy for ordinary people of ordinary intelligence, so I feel sure that his general advice was the same on marriage as on anything else: Ask yourself what will happen if you pursue a particular course, and if can reasonably be anticipated to lead to more pleasure than pain, then it makes sense to pursue it. Of course marriage (depending on society) has more long-term and deep consequences than most any other relationship, so you should be particularly careful. But "be particularly careful to examine your circumstances" does not change the general rule, which is to do your best to anticipate the consequences and act accordingly to pursue the happiest life possible to you.