How has he acted like he is above the team? What over the top celebrations? I've seen him be incredibly excited for a goal but I've never seen him do a dance over a flaming stick or anything. It sounds like their relationship is actually fine now but Therrien is as much to blame with his handling of Subban and any friction there.
Therrien is certainly not an uncontroversial coach either, if you care to learn more about it I recommend "Tales of a first round nothing" by Terry Ryan. A very interesting read.
I would also count Subban as an elite defenseman, he may not be as complete as Weber but he is also not as one dimensional as Mike Green. He is definitely a game changer as seen in the series vs the Bruins. I think Subban is much more of a team guy than he is given credit for. He is no Yakupov by any stretch.
Even without additions this team will improve as the kids gain more experience and confidence. Smith and Dekeyser will be a year older and this should help. Now I dont expect much improvement on the injury front as this team is still terribly soft. On the other hand it cannot get much worse can it? The Red Wings is a playoff team with the current roster. Will be interesting to see if any deal can be made and if Mantha can compete for a roster spot.
Babcock should have the team look at the powerplays of this series. The defensemen launches rocket one timers on goal every chance they get. It takes forever for any Red Wing defenseman to get a shot off.