'Ohana (dinner) would be our least favorite of the three. The atmosphere is great, the food OK, but it wasn't stellar. Dried up meat on a stick, in my opinion!
Boma (dinner) is one we eat at EVERY trip and we've been there I think 4x for dinner and 1x for breakfast. If you have a flavor for trying new things, I highly recommend it. If you and your party are picky, don't do it.
Kona (dinner) is another one of our favorites and I think we've been there 4x. We were just there last month. Have never been disappointed there. It's kind of a best kept secret because people are always clamoring to 'Ohana. We walk right up to Kona, check in, and get seated. We walk through the SEA of people next door who are waiting for their table at 'Ohana. The food at Kona is a mix of Asian/Polynesian. Not a ton of choices, but all they have are high quality.