I have been playing this game recently with my dad PBEM (Play by email). We played it a lot hotseat when I was growing up. My dad plays it a lot against AI, but I only play it against humans opponents. Dad says a human opponent is much more enjoyable/challenging than AI- because the AI is stupid basically.
I enjoyed reading your strategies/comments and there is so much I want to say in reply so we will see how far I get:
fahbs: -Research not worth it
I just don't see it paying off before the game is decided. If this was a long game between two symmetrical sides, then I could see research being worth it. But as the Axis, you're blitzing the Allies hoping to get enough plunder and crush them with your superior starting army before the US and USSR declare war. As Allies, you're desperately throwing up every wall you can to delay the Germans until the US and USSR enter the war. Neither side can afford to divert points to research.
Firstly your comment about research. You do go on later to say that some research is worth it and some isn't. This is my conclusion too. If the game is a long one then research is always worth it. I almost always play as the allied player. So I can only speak from that perspective. I tend not to spend money on research for France, because France surrenders before it is of any use
The research I find of most use.
Anti tank
Jet aircraft
Long range aircraft
Industrial tech
Rockets
there are too many of these to get them all. So I specialise as the allied player.
Everyone gets Industrial tech (cheaper repairs and purchases - this does pay off)
Russia and America get Anti Tank
Russia gets rockets
Britain gets long range aircraft and jet aircraft.
The other comments about research: It can be extremely frustrating as it is based on chance and so it is possible to never have it pay off.
Also once you have completed all the research in a category (say industrial tech) you can reclaim the MPPs you have spent (at 50% value)
fahbs: -Airpower not worth it
Just not worth the cost. The only point to air fleets is finishing off a weakened ground unit you can't reach with any of your ground units, but then you'll likely be intercepted by an enemy air fleet so air units just end up sitting around in a stalemate not being used. Strategic bombers are also way too expensive. You will never inflict enough MPP damage on the enemy to recoup the cost of the bomber.
-Carriers not worth it
This falls under airpower since carriers are treated exactly as an airfleet but with naval unit movement rules. They can be intercepted by enemy air fleets which sinks the carriers! Since they're almost twice the cost of air fleets, it's a horrible exchange.
Air power is a tricky subject. I agree Strategic bombers are useless and expensive. I always disband the bombers that Britain starts with (you get a fair bit of $ for it).
However you don't seem to be using the other planes correctly. The point of air power is to target a single unit so that it can be killed in the one turn. (if a unit is not killed it can be repaired to full - this is done at half the price of purchasing a brand new unit) if you can only attack a unit with 2 land units you are unlikely to kill it, but if you have 3 planes to assist it greatly increases your chances of destroying it.
You want to get your planes experienced, this increases their effectiveness and decreases their chance of taking damage (reducing cost). So make sure they get the kill as much as possible (bonus experience) and avoid intercepting enemy planes.
Finally the allied aircraft carries are weak early, but become incredibly powerful in the later game. So I tend to get them experienced by flying missions against garrison infantry. When you get long range aircraft this increases their strength as well as their range so very important for the british. Keep them away from enemy planes until they have more strength and experience.
Hope this helps and I'll come back another time and write some more