From: PDX (and now) London, UK
Another way to learn the japanese economy is to read the first few months of several IJ AARs. Everyone usually spells out what they're doing and gives info on which planes are being researched, etc.
About R n D, as Japan, you can control it. Choose Realistic RnD ON, and then you don't need any HR, just only move things forward as much as you like. Even to get early planes forward a month there is a significant investment in RnD. If you don't care about getting them early, don't invest as much research.
For the planes that arrive in 43 onward, you can pick and choose which you value and want to move forward. With a normal Japanese economy, you won't be able to push more than one ahead more than 6 months anyway. It requires a big investment of supply and HI. So anyone who does do that takes a hit elsewhere, unless they happen to own China AND India while doing it. That is most likely how rader was able to push some planes so far. More resources.
You'll hate it at first, but love it as you go. It's very fun to chose what ships to build, how to allocate your resources and RnD, and setting up the process of getting it all back to the HI. You'll also like starting out on the attack. It is like a tightrope walk and you have to constantly adjust to keep your balance.
"Success is the ability to go from one failure to another with no loss of enthusiasm." - Winston Churchill