With Chychrun, Chabot, and Sanderson - we don't need a dman that needs to be sheltered in the bottom pairing role.
Trading him for someone like Jeremy Lauzon would be ideal as he would pair well in a defensive role with Harmonic next year. That, or maybe Kleven will be ready.
He's just wasted talent in Ottawa that's all
He's sheltered because he hasn't gotten a lot of quality teammates. He mostly played with Holden and Zaitsev this year (a lot of Josh Brown before). When paired with a Zub for example, it allows him to play his game a bit more and to express himself but if played with Holden, he has to keep it simple and move the puck.
I don't think trading him for Lauzon would make the Sens a better team. He has a better frame but doesn't have Brannstrom talent and puck moving ability. I guess it depends what you need but if you pair Brannstrom with a Luke Schenn for example, you have a pretty good 3rd pairing and to beat the good teams you need a very solid overall lineup
Kleven should spend 1 year in the AHL, needs to learn the pro game
Eventually, when he gets more expensive and ready to take the next step then we'll see but if the big 3 is still there, then yes it might be time to move him. But for now, no rush as long as he's cheap