Teak: Classy looking, expensive, moderate maintenance depending on your choices, considerable additional weight relatively high on the boat.
NonSkid: Using
paints/gels/etc. produces variable results with large differences in nonskid effectiveness, and appearance. Some produce such aggressive nonskid that you wouldn't dare kneel on it wearing shorts. Others look great and don't tear things up, but may be less than effective nonskid under all conditions.
Colour: keep in mind that dark colours can get unbearably hot underfoot
Treadmaster - maybe a good compromise all around.