[JLMounce]

What aren't the brakes doing now that you need them to do better?

Do they not feel good, but stop decently?
Are they not able to lock up the tires?
Are they able to lock up the tires, but you feel the braking performance is sub-par?
Do they brake well but get hot and fade quickly?

Lots of possible avenues without needing to change wheels, but you have to know what you're trying to achieve.