I also remember "The Great Pacific War". I used to have a copy but it has disappeared in the past 20 years. Several interesting items that struck me when I first read it: (1) use of armor piercing poison gas shells in BB actions, (2) significant use of rigid airships (I remember a USS Memphis in particular), and (3) surprisingly sympathetic portrayal of Japanese - patricularly their strict adherence to Geneva accords regarding treatment of POWs (Hah!). I sort of remember it as a novelization of a Plan Orange scenario, not about island-hopping per se.