I haven't fully romanced anyone else other than Lae'zel, but I also think Wyll, Gale, and Karlach seem like good candidates for a sex-less romance.
I've played Wyll's romance with dark urge, I don't recall all the details but I think it can be played with no sex happening. There is only a dancing scene in act two, and in act three you can tell him "not yet", and that you want to wait.
