I did my flight training at Flight School Hawaii. They have a great programs there that fit anyone. Wallace is a great guy. There is some great potential to build twin time there with there Aztec's which I miss dearly. Give them a call or go to
www.flightschoolhawaii.com
IFR flying in hawaii is pretty boring. Go to the FSS at the NW end of the field and ask for the preferred route list. This will tell you what you WILL get regardless of what you file. I still have mine for nostalgia. Keep in mind that there are only 14 airports in that state and 11 I think that you can land at. The grind can get old, but as a CFI, it will allow you to focus on teaching more since you already know what is going to happen.
As a student in Hawaii, it can get damn intimidating. However, it will make your students AWESOME on the radio and get the exposure to working with several layers of ATC and with commerical operations. I highly recommend it.