How do bonus actions and reactions work in RTwP? They are an integral part of 5E.
This alone is a good reason why this game must be turn based.
Back to topic:
I disliked the initiative system of D:OS2.
Each character rolling for initiative independently would probably be best.
But I can understand why they did it turn based. It makes combat faster and it makes it easier to coordinate as team, especially in multiplayer.
Maybe the problem is that the game tries to be great for single player and multiplayer at once which leads to some strange things.
For example I disliked that you cannot pause the game in DOS.
Prof. Dr. Dr. Mad S. Tist 
