Traditional dobaks have an open jacket that overlaps in the front from left to right. Some Taekwondo organizations have adopted a V-neck, pullover style jacket. Sleeves are short to prevent the fingers from getting snagged in them while using open hand techniques. Some karate styles use even shorter sleeves and pants to make it easier to move when in close-quarters sparring.
Dobaks are usually made of cotton or a mix of cotton and polyester, sometimes referred to as “polycotton”. Some heavy weight uniforms are made from canvas and heavy drill cotton.
Some "masters" wear uniforms with so many colors and accruements that they would put am Aztec high priest's ceremonial robes to shame. It is best to to just wear the traditional white uniform with a few discreet identifing patches. Let you knowledge and skills define your expertise in your art. If crowd of martial art novices were watching a group of martial artists wearing only plain white uniforms and no belts performing patterns and sparring, the people should be able to identify the masters from their skill level.