Left defense:
As of right now, we have Brannstrom, Wolanin, Lajoie, and Reilly signed for next season who will be pushing for an NHL spot, along with Chabot who has the 1D spot secured, and Alsing who I'm not factoring into this at all. There's also Borowiecki expiring after this season, who will probably be given an extension since our organization loves him, he's basically the captain, and he's been playing well this season. I'm thinking that Brannstrom gets one of the spots, which leaves Wolanin, Lajoie, Reilly, and Borowiecki fighting for that last spot. Reilly I'm thinking either gets buried for $425k next season, or gets bought out for $500k for the next two seasons. Borowiecki is old enough that we don't have to worry about his development, so I think he should be 7th D. This means that either Wolanin or Lajoie will be our other LD. It should be Wolanin since he has proven that he is the better defenseman, unless he doesn't bounce back from this injury. It could also be Lajoie since he is two years younger and is more suited for a 3rd pairing role, so will ask for less money than Wolanin. Whichever one doesn't get the spot should be traded to a team looking for defense, like Winnipeg. Lajoie could also be kept in the AHL for another season but there's no point in keeping Wolanin down there for his 25 year old season.
Right defense:
On the right side, we have the opposite problem. We only have one NHL level right handed defenseman signed next season, Zaitsev. I do think that we should extend DeMelo long-term since him and Chabot are like Methot - Karlsson lite. The remaining spot should go to Jaros, while Thomson, Bernard-Docker, and Guenette tear up the AHL. I'm assuming Hainsey retires after this season, and even if he doesn't, there's a chance that he's traded away before the end of the season, so I'm thinking his time in Ottawa is almost done. It is also time to move on from Goloubef since most of the fanbase hates him (though I don't think he's been as bad as everyone says, he's slightly below replacement level but that's to be expected).
All of this is also assuming that we don't trade for another defenseman this season.
Reily will proly be traded next year, and they was playing Wolanin on the right side before he got injured, they may bury Zeitsev like MTL does with alzner.