I'm not satisfied

[Didz]

I did manage to complete an Austrian campaign, but only by playing like a psychotic idiot.

The trick seems to be to maintain massive garrissons in every provincial capital (the quality is less in important to the AI than the quantity) that dissuades some nations from declaring war, and encourages the AI to adopt Ghenkis Khan style raiding tactic's instead of attacking your cities.

You can then expliot this by pouncing on the small scattered raiding units and defeating their armies in detail rather than have a major battle. You will end up at war with everyone around you whatever you do so diplomacy is pointless.

Just smash everyone and everything around you.

Don't bother offering peace because even if they accept it they will declare war again in a few turns, just destroy everyone, until you have no enemies left alive. If you have any protectorates or reliable allies (very unlikely) then you can gift these wasted provinces to them so that they act as a buffer state.

I managed to use Wurtemburg and Bavaria in this role quite successfully in my campaign.

Oh! and forget trade and the Austrian Navy, certainly in the early stages of the game they are just a financial drain on your economy and likely to attract even more hostility at you from other naval powers. I actually scuttled my navy and forgot about it.

One idea I did have but haven't actually tried yet, is starting the Austrian Campaign by declaring war of all the American and Indian factions that you know you will never ever meet. I'm pretty sure that this will fool the player hate routine into thinking it has the upper hand, and might trick it into leaving you alone for longer in Europe.

Might be worth a try anyway, but basically forget strategy, ETW is just a slugfest. Fortunately, its pretty hard to lose a battle, in ETW so as long as you can keep your cities open and producing troops you should eventually win.