Hikari isn't a bad brand (top 5 in my books) but they use traditional (****) ingredients (like most brands). When you use these types of foods, there is a lot of waste, and worst case can cause constipation. Hikari Tropical also leans toward the herbivorous side slightly.
I use Omega One Tropical for my staple food, the ingredient list says it all. Many decent brands also formulate a food specifically for Bettas though, and that would be my suggestion. There will be less waste (depending on brand and your fish) and you won't have to alternate foods as much. Some Mysis or Daphnia (freeze-dried if possible, not frozen) as a treat once in a while is good too.
Freezing the food freezes bacteria, fungus, parasites, cysts, etc that may contaminate the food. Freeze drying or dehumidifying kills them. There have only been a few cases that I've heard about, but there is no control in place to avoid it. Also, Freeze-dried rehydrates much faster than dehumidified, and isn't hard and crunchy.
Freeze dried foods should still be rehydrated out of tank, but it takes a lot less time. Keep in mind that these foods are naturally 70-80% water.