It sounds like your native soil is pretty good for agriculture, and that state has a diverse and large agricultural sector. You might ask your local extension service what they recommend to add to your soil. But it looks like small grains, corn, beans, cucumber,sweet potatoes, strawberries, peanuts, tomatoes are all grown commercially, so you should be able to do a lot with your soil. Organic matter will probably help a lot. It will take time, but it will get better. It is actually probably easier than starting with heavy clay. If you have time you can plant a cover crop to add biomass or a legume to add both biomass and nitrogen. Your growing season is between 130-270 depending if you live in the mountains or near the coast.
If you have the shorter growing season, then you will need to start tomatoes indoors, but if you have a long season, you should be able to get a good harvest before the cold sets in.
Happy gardening in Hawaii. Gardens are where people grow.