Seems like the only complaint I'm hearing about the Tank soul is that it sucks having the units stationary for 30 seconds. I like the idea of the tank soul, but I would like to see it reworked.
One idea that came up that I found interesting is instead of the units being stationary, they default to the pathing of the unit with the tank soul equipped. As in all units within the defensive shield of the tank soul are "locked" together, still receiving their defensive buff for 30 seconds, but can move and are able to use their abilities and attack enemies. I think this would be a lot more fun to play around with. 