If you are looking for offense, and believe he can regain the form of two years ago... he'd be a good catch.
Not even two years ago. He was on pace for 31 goals and 57 points through 32 games last season before he got injured. At the beginning of this season he was still feeling the aftermath of said injury, be it soreness, stiffness, conditioning, whatever. Now he's been playing a lot better lately, points haven't been coming as much because he's probably mentally off from the poor start to the season. That, and most of the team is pretty bad offensively this season apart from Fiala.
As far as the defensive side, he's never going to be great, but part of that comes with the territory of being a top offensive guy. You see it with Burns and Karlsson (note: I'm by no means saying Dumba is that level of player) and others like them. But if you're looking for a guy who play a shutdown role, it won't be Dumba.
I have no doubt he can rebound next season with a full offseason of rest, being healthy, and a good camp. I wouldn't be opposed to moving him, but if we're not getting a top 6 center back, there's no reason to move him, especially right now.