Honestly, 3 days on Oahu are plenty for Honolulu - get "reservations" for tours at Pearl Harbor in advance, and if you can, make a trip all the way around (Turtle Bay area on North Side is awesome).
Then, spend perhaps half of the remaining time on either Kuaui or Maui, and the balance on the Big Island. All are quite different, and both Kuaui and Big Island are less commercial / less expensive than Maui, but all three are worth seeing, but 10 days are probably only enough to see two (and not completely by any stretch).