Larian Studios Forums Divinity: Original Sin 2 Divinity - Original Sin 2 - Suggestions and Feedback Change the action point system back.

Balance is important for a single player game too.
When there is a large disparity between the effectiveness of some skills and archetypes, then players won't feel rewarded by using those on the under-performing side.
If a large portion of your content is avoided because it is unbalanced then your players will feel forced to play using the supported builds, instead of the style they actually wanted to use.
This leads to wasted development time as you worked on features that no one touched.

Since this is primarily a multiplayer game, this is an important issue. When a couple of members of your party feel significantly weaker than others, they're going to have a bad time.

On the original topic of AP, I believe a "fixed" action point system is a great change from DOS1. In DOS1 characters stacking Speed were able to take significantly more actions than others. It was the go-to stat. Having a fixed AP per turn makes this a lot easier to balance, and also doesn't leave characters with lower APs feeling left out with shorter turns.
Certainly we could scale this fixed per-turn-AP up to some other larger number, and this would make it easier to fine-tune some ability costs, but if abilities are balanced in other ways then the current AP system isn't inherently a problem.

On the subject of the new armor system, I have mixed feelings.
The current system prevents CCing the opposing team from the start of the fight, preventing them from ever getting an action, which is good. However, this problem is only delayed, as guaranteed CCs blanket anyone without armor later in the fight.
Also, Magic debuffs are suffering greatly. You can't do as much Magic Damage with Magic Armor up (can't apply Burning, Poison, etc.), but you need Magic Damage to tear it down.