I should like to point out that as Venice I got my ass kicked in by the Ottomans, after I already annexed and cored all of Naples. This never happened to me in EU3. This was with Hungary and Bohemia on my side of the fight as well, and with the new peace mechanic I had to really hurt myself to get peace (I couldn't give away a bunch of useless Hungarian land or whatever and call it that, I had to release nations and give up real territory). I fucking love the new ai, and I think eu4 will be the best paradox game yet. Yeah, there could probably be a bit more eternal turmoil and politics, and such, maybe make changing cultures, and cultures a bit harder, but that will be done in mods as it always is with paradox games.
tl;dr this game is amazing.