Yakuza is probably my favorite game series, and this all sounds so interesting to me. They are basically JRPGs at heart with brawler combat so the switch to a turn based system seems like it should work out ok but will be a very drastic change for the fans. Especially here in the west. Yakuza has just recently sorta broken through and become popular here so I wonder how many people this change will turn off.
There was a video that everyone thought was an April Fools joke but it looks like its just an early version of this.
If it takes positioning into account it could get real neat. In this video you see one of your party members get tackled to the ground, and then another one distracts the enemy. Now the first character is in a position to attack from behind which is pretty neat.
My worry is it bogging things down. A lot of times later in the game I'd get annoyed getting into a fight because it stops whatever it was you were doing and you had to deal with the fight. Even if it was over quickly because you are stupidly overpowered it could get annoying. Turn based fights might slow things down even more. Or maybe if you're powerful the enemies will run away from you, who knows. There are some things they can do about that.
They've made so many games that I've enjoyed that I'm very much willing to give them the benefit of the doubt that they can pull this off.
EDIT: another thing is the things I always remember from Yakuza fights are pulling off all the heat actions. These battles will pretty much be all that, nicely animated fighting rather than you swinging and missing and other silly things because its a video game. Might make fights look even better.