Knocked out a quick Burgundy game, ended up being far more successful than I could imagine:
Wore down France over the first 50-100 years, then vassilised > dismantled HRE > took Austria > vassilised = Burgundian Conquest achieve. Also invaded Britain, mainly to take London to secure English Channel trade hegemony, and also to acquire N and S American colonies. Switched to Netherlands once France incorporated as much more globally-orientated, got Sinasappel achieve and a few others.
Was pretty sweet to a) finally get Burgundy going properly, and b) be able to switch ideas et al from continental to global once Burgundian pre-eminence had been established in Europe.
I could have blobbed across the entire continent (I took Egypt, Japan, Taiwan and some other regions for various achieves), as I had absurd power (never had so much income or such high force limits, ended up at about 1k), but I got to the point of not really being bothered about it, as managing wars against, say, Russia, is just too much to bother with, for not much gain other than bigger blob. I'd have won, but moving 20+ armies and ensuring I'm not being invaded on the other side of the world is just boring for me. EU IV thrives when the challenge is there. It's extremly gratifying to meet and beat that challenge, but the game loses something after that. Is how it is.