You are pretty limited when it comes to hunters. All you will be able to see really is the collar of your shirt. The rest have to be traditional colors, which I'm sure you know. In hunters I like a grey coat and yellow shirt :)
Pretty much anything looks good on a bay! ;) I'm not a fan of red on them, unless they are a darker, seal bay or something like that. If your horse is more of a red bay, colors like orange and red could blend and look odd.
I have a seal bay and I LOVE him in yellow/gold :)
ETA: Good breed choice, you're smart!
Every great dream begins with a dreamer. Always remember, you have within you the strength, the patience, and the passion to reach for the stars to change the world. ~Harriet Tubman