Kronwall is a pretty good comparison for Smith. Both have elite offensive instincts, can play the body, and are at their best when they can skate. Smith likes to carry the puck some more and Kronner likes to move into empty spaces. Neither are PP QBs.
Both guys need defensive stay at home dman to be effective offensively. This is why Smith looks confused and bad when paired with Q, and Kronner isn't nearly as effective offensively when paired with a guy like Big E. Kronner's experience allows him to be a better player overall defensively, but he is not near as effective as he was when paired with Stuart.
Kindl is also an offensive dman, but he is of the QB mold. Lids vs Schneider/ Raffy. His game is all about puck control and running the offense. The PP can go through him. His defensive game is coming around but he isn't quite to the point that I'd consider him a two way dman. If he can learn how to better use his reach and vision, he'll become good enough to be considered a true two way dman. His game is a lot safer than Kronner and Smith and thus I think he could be paired with a two way guy and do well. Thats why the Dek/ Kindl pairing works.
Ericsson and Dekeyser are both two way dmen. Ericsson is still a forward playing D. He has just learned how to better use his body and reach to defend. If he was 6'0 instead of 6'5 I don't think people would be as thrilled with him as a so called defensive dman. I actually think his offensive skills are underutilized, as he has a booming shot and pretty good outlet passing instincts. Danny plays a very Lidstrom esque game. Its all about positioning and good vision, both offensively and defensively. As he grows more confident, I think his offensive game will come along more, more of a 30-35pt guy.
Quincey is just bad lol. He wasn't bad when he was playing a simple game as a defensive dman when he was first called up. Being given offensive chances in LA, Col, etc was the worst thing for him. He is a poor offensive dman, but they get paid more so he'd tried to mold his game that way. Now he plays neither well, and is an awful pairing for Smith.
Give Smith a guy like Matty Nordstrom, Brad Stuart, Brooks Orpik, etc and I think he'd look a lot better because he could play his game. This is the same thing that happened to Kindl in his first few seasons, only Babs likes Smith more. Until Kindl learned to play Babs system, he wasn't allowed to play his game. Until Smith learns to be a big Canadian defender, he won't be allowed to freewheel offensively, which he needs to do in order to look good.
I also think Smith is still a bit timid physically due to the suspension. Competition is so fierce that he isn't going to do anything that might get him suspended.