A good solution is just to have fixed gold reserves for international trade, maybe leave a small income from gold mines. So as Germany, if you want to rearm at a record pace you need to buy resources which costs you your gold reserves (because you cant sell your products in exchange because you need all that IC to rearm)... whooops, I'm out of gold in 38, what to do? Anschluss Austria with its gold reserves! Then Czechoslovakia! Poland is next, but UK&France guarantee its borders, so we need to secure resources for the inevitable war some other way. We got quite a lot of industry with Czechs but not many resources...so we trade resources for supplies/consumer goods with USSR!
The historical route will make sense this way without too much railroading. And this would also simulate economic mobilization somewhat, because you cannot count on conquest to refill your gold reserves as democracies, so you have to keep a balanced budget until war is imminent and produce a lot of consumer goods just to reduce dissent to manageable levels (Darkest Hour had a nice dissent mechanic, in HOI3 dissent is almost a non issue, only arbitrary numbers to allow arbitrary "better laws"). After war starts "allow debt" and "lend lease" will kick in so no need to worry about gold reserves anymore. But it will decrease score for the recipients (UK&France) and increase for the lender (USA), so it will also simulate the war's effect on the participants economy, prestige and power.