How much slash potential is there, do you think?
Hmm. Alasdair (the chief's son) is married and also quite worried about his wife during parts of the book. There's also a lieutenant (Francis) who is friends with Robert, but he's pursuing Robert's female cousin. And there's a Macdonald clansman whose life Robert saves during a hunt, and who swears him brotherhood, but he's a quite minor character. OTOH, Robert has no canonical het love interest.

Interesting! Yes, I had gathered that you like Mansfield Park a lot.