I love Lanai. It is expensive for food because you have to eat hotel food no matter what. Henry Clays is still not cheap either and you can charge your dinner to your Manele Bay or Koele Lodge room.
There was a small local eatery (more like a stand) but the nothing there sounded good to me.
I haven't been to Molokai yet. From what I heard I am not too anxious to go there (nothing bad just nothing real positive) however I will go because I have to go at least once.
Maybe go one or two nights to Molokai then spend the rest of your time in Lanai.