--Varsity numbers are generic as hell. I get how they work for classic teams (e.g., Celtics, Packers, Raiders, NY Rangers, etc.) but if you're a newish team or an expansion team, please come up with something more unique and original.
--The Padres' brown and yellow unis are trash. I like unique looks, but brown for a sports uniform? With mustard yellow? All you're missing is a corduroy jacket.
--Teams like using black for some reason (BFBS), but I also see wayyy too much white (what I'm calling WFWS). Especially in the NFL. Why does every team need white pants when white isn't a major part of your repertoire? Take the Ravens for example. Their colors are purple and black, and yet they favor white pants? And the Broncos: orange and blue, and oh wait, white pants?! Kansas City? Chicago Bears? Eagles? I could go on. Why not red pants or blue or forest green, and not just part time?
--Going off that, I love the look of one team color from the helmet to the socks. Nice and uniform.
--The Angels' look with Disney was one of their best looks ever. Fun font, the winged "A," vests, the whole shebang. Looked amazing.
--Teams should emphasize their geographical locations way more. See the Rangers putting "TEXAS" on both their home AND away jerseys. Same with the Miami Marlins and the Dallas Mavericks. Once upon a time team names were nicknames. That's why in old newsreels you'll see teams being named the Detroit "Tigers" with quotation marks because the team's primary identity was with the city, not their mascot. These teams represent their geographical location. What's more important, the city a team is from or its name?
