Here comes my opinion and stupid thoughts.
The Hawks are in no hurry to sign him as they are in the catbird seat. They don't have to sign him right now, or during the season anyway. He is an RFA, and offer sheet eligible. Is Seabs worth 5+ mill? I think so. Kieth is locked up for 12 more years at an average of a little over 5 mill. Keep in mind he is getting 8 or close to it this year.
Seabs doesn't have the goals/points that Buff has. I am not sure Buff can keep that pace either, year in year out. Time will tell. Seabs brings a good hard-nosed style to the ice, has some decent vision, and is I believe a vital cog in the core. He can score, and does. Last year I called him Mr. OT because it seemed like whenever we went to extra time, he scored.
With his RFA status, he could receive an offer sheet. It would have to be at least 5 million or more for him to even look at it. Assuming that he signs an offer sheet for that amount or more, the Hawks would get a shit ton of pics.
WITH ALL THAT SAID, AIN'T NO GM GONNA DO THAT. It would destroy that teams future for a long time to come.
I am not worried about it at all. I believe he wants to stay here, he wants to play here. He does have some deficiencies, like all players do, and Duncs bails him out as much as he bails Duncs out. If he left, unless the team he went to had a Duncan, Seabs would be exposed big time.
Again, my opinions. I am not in negotiations so I couldn't tell you anything.