the fact that this is based on 5e D&D and is already confirmed turn-based, I don't agree with team initiative, it just seems like it will lose the feeling of the whole game. The most glaring issue is balance...it seems like the side that goes first has a huge advantage. Since they are wanting this to be as similar to PnP as possible it just doesn't make sense. If you win initiative, you can focus fire and take out bosses or the stronger enemies in one single round. This is very uncommon in PnP as initiatives, on average, are broken up allowing everyone to at least take one turn before potentially dying. I understand that it supposedly allows for more cooperation since one player is controlling the whole party, but you still can have that in character-based initiative.
Larian wants it to be as close to 5e D&D, but not in the way sense some hardcore fans would - they are not simply copying mechanics into digital setting with no consideration for the medium, and they are not afraid to make changes, if they feel they would make for a better experience. While one might argue against need for some changes, the core principle is sound.
Balance is a valid concern. This might lead to rewarding Alpha strikes - doing as much damage as possible before enemy gets to act - that is FiraXCOMs problem, where combat initiation has the most overwhelming influence on the encounter's outcome. Perhaps, something like Pathfinder:Kingmaker turn-based mod system could be implimented? In it initiating party gets only half actions in the initial attack - which means some damage and moving into position, without a full turn of slaughter.
