I've given thought to the same question, and have seen in another thread where someone recommends taking an early morning flight to give yourself the full day on the island you're traveling to. Plus, in their opinion, flying mid-day eats up too much time between commuting to/from airports, fly time, etc. They feel it's wasting a day if done any later than early morning. I can see their points.
That being said, we've opted to go the same route that alohamom recommends. We're taking two inter-island flights and both are around 11am-12pm. It will allow us to sleep in a little, grab breakfast, get to the airport without rushing, and by the time we get to our next destination, it should be close to check-in so we won't have to wait around for our room for too long.