tl;dr; Warfare not being the focus, nice. Warfare being neglected, not nice.
I'm really not fond of the war micro in any (older) Pdx title that has it, and I'm all in for automation. But the thing is, while warfare is present, it's not really part of the gameplay. If you think about it, when the Diplomatic Play ends, generals are affected and war starts, you pretty much know who will win -> alliances, technology, supplies, number. It all depends on pre-war actions, there is no real decision making in warfare (except for naval invading the enemy capital).
Warfare not being THE focus is perfectly understandable and there are already other Pdx games where it is the focus, but it got to be A focus, since as it is in the game, it still has an enormous impact on countries and pops. It doesn't need to be at the center of the gameplay, but it must be part of it meaning that you should be able to interact with it. i don't know, give objectives to generals (like taking your claims rather than a meaningless state, or hitting armies bases/weapons factories if it had any impact), select stances with various modifiers like advance speed, kill rate, sparing civils, target supplies, scorched earth, etc... (you kind of have this with late game specialists, but that's not really impactful and unwieldy to say the least, and it's only beginning at tech IV).
The worst part is that there STILL IS MICRO, since you got to babysit your fronts and generals, because a front might break in two, your armies go to one and the enemy go to the other, which means they could make a dramatic unopposed advance, you also got to quickly reassign a general after a successful naval invasion (no it wasn't fixed).
Just look at the graphical representation of it, those sad little encampments shooting at each other... Why not having some small guys shooting at each other, advancing on the map ? Everyone says warfare is not the focus of CK3, yet you still got those really neat little sparing guys. you might think it's just a detail, but I think it's just another sign that warfare was just neglected, and that's hardly defensible.