I saw lots of coloured yarn and mane charms in the hunter and eq rings at Ontario A shows this past summer.
Lots of different coloured jackets in the hunter ring as well.
You can get shirts with fun patterns on the inside of the cuffs and collar. Traditional in the show ring, fun when you’re warming up.
You can always pick up a fun belt or buckle as well.
“Pizzazz” in the hunter ring usually shows up when the shadbellies some out. Bright linings, fun points. I have a set with bucking horses on one side, and a metallic paisley print on the other side.
Personally, I’m not a fan of the yarn and charms. Like @MHM said it breaks up the topline. But I’d love to add a colourful jacket to my collection. RJ had an almost turquoise one, but I couldn’t find it anywhere in person. Now I can’t even find it online in my size.