Naval b'rshut haTorah

Dov wrote in his post that "while there might be ethical requirements beyond the requirements of halacha (like the famous Ramban a"ht which describes how one can be a moral failure while still keeping all of halacha), the Torah can never be immoral".

Your citation of the Ramban is interesting. Here's how Chavel translates the passage at the very beginning of Parshat Kedoshim:

The meaning thereof is as follows: The Torah has admonished us against immorality and forbidden foods, but permitted sexual intercourse between man and his wife, and the eating of [certain] meat and wine. If so, a man of desire could consider this to be a permission to be passionately addicted to sexual intercourse with his wife or many wives and be 'among winebibbers among gluttonous eaters of flesh' (Mishlei 23:20) and speak freely all profanities since this prohibition has not been [expressly] mentioned in the Torah and thus he will become a sordid person within the permissible realm of the Torah (naval b'rshut haTorah)!

So really what the Ramban is saying is that were it not for this commandment of "be holy" then it would have been the case that one could be a naval b'rshut haTorah. As it turns out, though, the Torah forbade such behavior, and thus it is impossible to be naval b'rshut haTorah because those loopholes have been closed off by this general law. Just to restate: one can't be a naval b'rshut haTorah after "be holy" because one is no longer acting "b'rshut haTorah."

So I'm not sure that the Ramban is a good case of someone who would say that there are ethical requirements outside of halacha.