It's looking like the new patch is going to change all the military options to Quantity>>Everything Else. Army quality seems to suck really bad in comparison to pure numbers both in terms of intimidating the AI into running away or in simply winning battles. Fort meta means you're going to spend tons of time sitting on high level forts which is a massive drain on manpower. And since army quality doesn't matter a whole lot, any siege needs to be babysat with extra stacks if the enemy has any decent size armies. Example: By 1650 almost every fort in Europe is Level 6 which means you'll want a 40 stack to siege a single fort. In order to prevent the AI from crushing that stack you need to back it up with another 40-60k or else the AI will jump you with a 60k army and completely crush you. So you need about 100k to "safely" siege an enemy fort. And the manpower bleed of sieging level 6 forts by 1650 is brutal as well. All this adds up to Quantity looking like the premiere military idea group and often a good pick for 3rd/4th idea group.