Let`s see what should be the best buyings on Japan 1.
1) 3 transports, 1 marine
A pretty powerfull combination for striking allied islands soon.
2) 2 transports, 1 IC
Combination of both island striking and land expansion in the Asian mainland.
3) 4 marines, 1 sub
Using cruisers and bats to the maximum plus one more sub is a powerfull buy.
4) 1 des, 1 sub, 1 IC
Strengthening the navy plus the land expansion in the Asian mainland.
5) 2 transports, 1 bomber
Striking allied islands plus bombing their facilities is an interesting buy.
6) 2 transports, 2 subs
Striking allied islands plus sending cheap units into sea battles and convoy blokades of the allies is a good buy.
7) 2 transports, 4 infantry ( or some other land combination for 12 IPC)
Since Japan starts with 3 transports and 12 land units in Japan, after deploying 6 of them on rd 1, it has 3 transports, and 6 land units on Japan left. With 2 more transports and 4 more infantry, it can deploy 10 units to SE Asia on rd2. (Japan can take along an infantry from Okinawa and/or Iwo Jima so the buyings could be 3 art, or 2 tank, or art, marine and an inf).
1 AC, 2 marines
Interesting combination of strengthening the navy plus boosting the island taking power.
9) 2 des, 2 marines
Similar as the last one, just with less air defence but more blocking power.
10) 1 des, 1 sub, 1 tra, 1 marine
Strengthening the navy plus the island expansion in the Pacific.
Moderator’s edit: Added tag [House Rules] to title.