I was in your shoes two years ago. Kristy's deck was starting to chip where the gel coat was too thick. I was afraid that a new coat or two of paint would make the wonderful original nonskid less effective. I don't like the feel of painted-on nonskid. I opted for a PVC product that glues down to the deck after it is faired (to fill in the grooves) and sanded. Before I bit the bullet, I saw a few jobs in person and spoke to two owners who had the product on their boats in the Caribbean sun for 9 years, and said it still looked like new. It's 1/4 inch thick, tough, repairable, easy to clean, has even better nonskid properties, and looks great. The material including glue weighs about 200 lbs. An added benefit I wasn't expecting is that it insulates in the sun to lower cabin temps by 5+°F.
It is expensive, ~$25K, and you have to find an installer who measures by hand (that non-stretch plastic is used to make a template, then the panels are made in the shop). Avoid installers who use a computerized laser to make the template. I saw several like that that were not satisfactory.
Kent & Iris