I'm guessing the following are untouchable due to their skill, sure, but also marketability and being the face(s) of the franchise in the eyes of new ownership as they transition to the DT core (it won't be a quick process): Stutzle, Tkachuk and Sanderson. To a lesser degree, Batherson too, simply due to his contract - hard to find his level of skill at that price point.
I think it could be Norris or Chabot.
Norris simply due to injury history and the financial commitments made to him. Excluding this year, in the past four seasons the total GP's per season were: 50, 8, 66, and 56. When you take the contract into consideration, I could see him viewed as a risk from a business perspective because of this alone. But let's be honest - he's good and young, and new ownership does not seem as concerned about this as the previous owner. I could see him being moved but only for a legitimately good deal that makes sense for the Sens, for both now and in the future.
Chabot... I don't have a write up for him, this is more of a gut feeling.