RSRD is historical. As stated, early war better to start from Manila. Historically most action is there and for the next several months moves south to Borneo and Java.. In fact many large invasion fleets will invade the Philippines the first month of the war. If you start at Manila, you should get a patrol star for one, but easy to go sit in Lingayen Gulf and you'll get ran over by several invasion fleets.
In Jan 42, lot's of action near the ports of Borneo. The big action takes place near Java in late Feb, seems the 25th...Just patrol a lil WNW-NW of Surabaya Feb 25th-29th...One invasion group contains over 50 ships.
In 42, you'll want to study and find the historic battles, but most the action is near the Solomons. They're several large historic battles that take place, such as Coral Sea, Santa Cruz, Eastern Solomons, etc.. In Oct-Nov of 42 if you hang around Savo you'll run into so many TF the only decision you'll have to make is which one to attack.
1943 is a lil tricky, near Truk is good, Bismark or historic shipping lanes. The best lanes are Formosa and about 30 NM's off the west coast of Borneo, just sit about 30 NM's away from Brunei Bay.
The best lanes in 44 are the same as above,
1945, hang near the Korea Straits.
Obvious many battles take place elsewhere that you can get involved in if you study up.
Every action or battle listed in the following link is included in RSRD.
http://combinedfleet.com/battles/
Two good maps for early war, pick a date and an ambush point
May have to save them to "My Pictures" and magnify them for better viewing
If you start out of Pearl at the start of the war, hang south of Wake, but you want action..Manila is better.