weak. Oregon, hands down, has the best "brand" in America. I travel extensively for work and no matter what state I'm in I see Oregon gear being sold. The Oregon O dawns car windows in every state in the country.
Teams like Baylor, TCU, Maryland, and even Utah (who cleans BYU's clock in State for merchandise selection and sales) are building strong brands.
I put BYU's uniforms in the class of Alabama, Oklahoma, and Penn State. These schools uniforms are traditional but not "cool". These teams have very traditional support from fans but are not exciting or attracting new fans.
BYU needs to attract new fans in state, and recruits from out of state. One way to do this is to modernize the uniforms (within reason) and release new and exciting gear for fans to purchase. Alternate uniforms should be different and serve to market BYU.