I think something that might improve the naval aspect would be to model the different carrier classes. I think, not sure, that the 3 navies had 2 different class carriers, one large and one smaller, escort type carrier. (correct me if I'm wrong) The large carriers, complete with a largers escort fleet (2 cruisers, 5 destroyers) could launch all navy aircraft at the expence of speed. The escort carriers were faster, but could only launch lighter aircraft (A6M, light F6F, Seafire) as well at PT's and LVT's.
I could be wrong though....