See I don't agree with half of that. You're not increasing difficulty, you are hamstringing yourself and limiting game play options.
Not to mention increasing the way CC works affects both groups, both you and the enemies. So that to me is a non factor and honestly works more to weaken them than you.
Honestly its AI or bust..numbers are just numbers, if all you want is numbers then go download Rhidian's mod..higher heal cooldowns, -100 resistance to start game to all elements, all enemies have a boost to vitality, willpower and bodybuilding, summons are interesting because he added utility skills ot them to fit their element but with a super high cooldown.
I saw a couple people saying asking for AI is like asking for the moon, but let the modders get their hands on the nuts and bolts of the AI. Reconfigure it, BG2 was not NEARLY as punishing until people got their hands on it. Then all the sudden enemies started casting new spells, using their potions and wrecking you..
And I don't agree with this.
Numbers are just numbers? The whole game is numbers, difficulty easy are hard are predicated very much on the numbers. The numbers are key to balancing, you suggest they don't matter, which isn't the case. The examples you give do change strategies, higher cooldowns, yep. More damage per hit, yep. Those things can change everything. I look at balance two ways... I have a lot of options, but are they good options or do I have a few good one's and mostly bad one's? If I have that, I need to balance those between each other better. When done with a fight, was it a challenge? was there a legit chance to lose? I try to get both of those, the more viable options I have the better, the better the fight the more interesting it is.
That said, yes adding more skills or adjusting the AI on how they do things plays a factor to and not against that. Adding skills isn't hard to do on our end fwiw, but the time to test it all out... can be pretty daunting. If Larian does it right they have tools to bounce to any scenario at any point to test, we have to play it out along with the story... time.
I've found nerfing CC more a benefit to the enemies as they weren't smart enough to understand that A1 is Crowd Control, where we know how important it is. So the nerf hurts the player more because we would exploit that because of the advantages. And we can only take so much of enemies CC on us before players would get pissed off. CC is good in PvE when you are using it, it is hated in PvP because downtime sucks and blows. Many enemies have no CC abilities and if they do it, it isn't A1 to them all the time, they use it much more sparingly.