The suede material sounds much more conservative. Black would be completely acceptable. I don't see a lot of navy and it wouldn't be my personal choice but I don't see why it'd be a huge problem as long as it's dark. Like I said, when it comes to the eq ring I like my students in traditional colors/equipment. If you see the upper level classes/medals just about every single rider is in a navy coat/white shirt/beige breeches/black helmet. There might be some more variation in the hunter ring but it's still a pretty conservative discipline. GM always hounds on the fact that your dress and your tack should always be very conservative so that you can highlight your horse as the star. While my GPA has the silver stripe down the middle I tend to err on the side of conservative and leave my fun stuff for schooling or local shows. That's just my opinion though! If you love the lizard skin I'd ask your trainer and see what she thinks. If she's ok with it, go for it!