I really dislike the look of the Prince Charlie jacket with a neck tie (Sir Sean Connery's preference notwithstanding). The style and cut of the jacket demand a bow tie.

If you don't want to wear a black bow tie, maybe get another color? Grey or silver, perhaps? Bow ties don't have to be "formal" you know.

If you absolutely have to wear a neck tie, then I would say go for the rouche tie option, as shown above. I say that as someone who dislikes the rouche tie in general, but be that as it may it has become a somewhat common look with the Prince Charlie jacket and so it probably wouldn't raise too many eyebrows.