Dahlin makes the most sense. He is a #1 overall pick and a fierce competitor. He doesn't have ties to the area, doesn't have a grouping of close friends on the team (especially with Casey being traded), and is spending his prime years wasting away here.
Thompson - Was given the opportunities in Buffalo to excel, got a decent contract, and has children and a wife who has already had to overcome cancer. This area is great for kids, and we have close proximity to Roswell, Cleveland Clinic, etc if the need ever arises. That matters.
Samuelsson - Got a nice secure contract, seems to be a fixture of this group of players. If his play recovers, he may want opportunity for more minutes elsewhere, but he is probably an okay middle pairing defenseman or a great #5.
Cozens - He grew up in the middle of nowhere, so hopefully Buffalo doesn't seem too bad. He has friends that he grew up with on he team.
Power - Owen Power could eventually want to be a number 1 elsewhere, but I don't see it happening before Dahlin needs to get out.