I absolutely LOVE the turn based system I think it is super promising and I could see myslef having a couple more playthroughs of the game (if not more really) with this mode. But as many players I have a big problem with how rounds are handled and turn order in general. I have seen many parallels being drawn with other games whether they are traditional RPG or videogame adaptations and to my surprise many people are thinking that it wouldn't be possible to transfer the system to a more "fluid" turn order system.
But why ? Quite a few videogame RPGs have a speed system determining who plays when and how long each action takes. The tactics ogre game(s), final fantasty tactics, heck even FFX had a similar concept (and technically every ATB system is kind of the same story really).
Each player starts with a value of 100 of Initiative (or whatever you want to call it) and depending on their speed (for Pillars it would be action speed and recovery time basically) they would lose X unity of Initiative per turn (a turn being any character on the battlefield playing an action). That way fast characters can play more often than really slow one and action speed and recovery time make sense again.
Now some people raise concerns regarding buff/debuff and crowd control times. And again, I don't really understand why. You can do it a couple of different ways. Either you base it on the caster's "tempo" (basically durations would be based on the caster's ended turns), you can base it on the target's "tempo" or on a global "timer". A global timer can be quite easy to make and represent and would be for instance every 100 units of Initiative (obviously this is an arbitrary number). I don't think there's one better solution as such, basing the duration on the target's is the easiest to grasp and play with and to balance in my opinion but a global timer can work too.
And to the people that would argue that basing the durations on the target would create balancing issues I would just reply that it would actually give another reason to tinker with your speed and recovery time. Also it would guarantee that every effect has a "global" effect similar no matter the target. If you poison Sonic and he plays real fast he will suffers the same amount of damage, in a shorter amount of time yes but the same amount as Bob the turtle who took twice as long to act and suffer the poison damage.
All in all I think it's very realistic to have speed impacting how often characters play.
Now the real question is whether Obsidian did the first iteration of the turn battle system like that because of technical limitations or not. Maybe it would be too much hassle to code into PoE2 a dynamic system and they can only do a global round system, I hope not because the current system makes some builds and archetypes extremly bad and overall being a super bulky turtle is the best way to play the game which is a bit unfortunate.
That was my two cent. Good job nevertheless and the fact that's it's a beta is encouraging because it means there's realistic room for improvement, so yay to that!