I think you are limiting his ability a bit. His job this year was to be Samuel Johannesson's partner. Samuel is a puck mover who is under 6'0" and very slight in build. He isn't much of a factor defensively, but is a pretty good "thief" stealing pucks. So his job was to be Carl Gunnarsson and let him be a puck mover. He had to be the big body on the ice. He was also excellent on the penalty kill. He did that very well. He was very Kasparitis like in timing a hit at least 2-3 times a game. That will make any forward think twice as to whether he is on the ice, because you don't want to take that kind of hit. The thing that goes underrated is his ability to make a first pass and carry the puck out of trouble. He is a decent skater and has a few moves up his sleeve. Don't look at the goal totals and say well he has no offensive skills. He is snakebitten and hasn't gotten the puck luck like McGing was all year. (Hugh McGing should've had 40-45 goals with the passes Stenberg, Robertsson, and Kaski were feeding him.) I wouldn't be surprised if Loof put up 7 or 8 goals next year kind of like Skinner did.
Tucker does have more offensive ability than Loof. Both make their share of mistakes with turnovers. I think Loof is the kind of guy you could put with a Faulk, Parayko or a Petro and they may or may not mesh. If they do, then their games will take off offensively and complement Loof defensively anchoring the boat on the 2 or 3 on 1s that they tend to leave their partner with occasionally Loof handles well. Loof will handle the front of the net for them and board battles. He would've looked a lot better in board battles at times if he had more support down low from the forwards as that was an issue for Springfield all year that led to a lot of shots on goal. (thank you Mr Ellis!) I don't see that as much of a problem in St Louis. I think he is blossoming into a 5-7 guy. Give him time.