You can go the semi-historical road. Considering the fact that you haven't built much IC, you should annex Czechoslovakia in order to get some more. However, Allied nations are, most likely, less mobilised than you are, so instead of attacking Poland early you could attack it in spring of 1940 while simultaneously attacking Denmark - that should give them little time to build big forces. By the end of your conquests Kriegsmarine would be ready for action and you could attack Norway and Netherlands and invade UK. After fall of UK conquest of France should be easy. Then you can think about your future moves concerning the Soviets.