Well, SilvrStar21, I'm a male and am probably not the best authority on these things. However, I attended a competition recently (as an observer) for college age students. They were competing for an opportunity to play with the local symphony, so the conductor and some members of the symphony were part of the jury. There were numerous female performers in the competition. They apparently were asked to dress as though they were playing with the symphony because they all wore formal dressware in every piece. As I recall the women wore a variety of outfits, including all black dresses, short sleeve and long sleeve, and various length hems. Not being female I have no idea how the different outfits affected their playing, if at all, but they all looked professional on stage. Have you thought about calling the local symphony office (in whatever large city is nearest you) and asking them for advice? I'm sure they would be very helpful. I have to admit, the medieval princess-look would make quite a stir.
Regards,
Richard