Consistency from the armour system really allow you to come up with more creative battle. The sad part is that there's a very limited amount of fights like that in the game. Larian failed to take advantage of a modern system that allows for much better scripted battles.
The easiest one being the final boss fight of Act 1. You have a bunch of hard enemies to deal with and sudden spawn of the 3rd faction that everyone must defeat. The map layout also allow you to be creative. That's the kind of scripted fight we need more in the game.
The armour system is fine. Lack of variety in combat is the main issue created by lack of creative skills and interactive battles. There's not a single time in the game you get to use the Balista they showcased. Man, imagine if there's a proper Kraken battle on the sea where you have to keep killing the adds it spawn and use balista to damage it while getting buffed by Lady Vengeance.
TOO BAD IT DOESN'T HAPPEN. When your entire gameplay is all about using the same attacks and strat, people will just find an easy target to complain about and atm, it's the armor system because that's where the strat of the entire game stems from. As there's only 1 strat in this game, enjoy using your most damaging combo to beat 99% of the fight.
No matter how I look at it I really can't see that to be true, even if the battles were scripted well. The act 1 boss was amazing, but I feel that was because of the scripting and interesting terrain. It would have been good with or without the armor system, which in my opinion only served to make the first half of the fight worse.
In d1, when a fight starts, you had to choose. Do you buff first, because buffs were actually useful? Do you try to cc the enemy, or do you try to apply damage immediately? In divinity 2 buffs are useless, and armor blocks every single useful effect and the enemies have massive amounts of it. The only remaining option is to start the battle applying max damage.
This is of course not even touching on the 4 ap/turn limit imposed as well. But I think that one example shows my opinion on how the new armor system limits options, not expand them. RPGs have always been about risk management, there is always a chance for battles to go awry. That's what makes them dangerous and fun. Having to think of a backup to your backup in case your house of cards falls is fun.
Having 100% chances of everything and battles going the same way every time might prevent the frustration of some. But the people who this is made for are those who don't want to even think of what to do if things don't work out perfectly, and would rather reload a save. Those are not the kinds of people I want the game to appeal to, personally.