There is a long history of trades involving high value players that are not deadline deals.
Contract, term, age, injury history, wanting-out, recent production, etc.. all come into it, but generally the Sabres will likely get three "assets". Sometimes there is some D level prospect involved but that is just filler. You also have to consider that the assets are only valued at the time of the trade, some trades turn out well for the seller (Yashin/Duchene/Karlsson), and some trades turn out horribly (ROR/Seguin)
Asset #1: A good or great pick/prospect/player.
Asset #2: A good to okay great pick/prospect/player.
Asset # 3: An good to bad great pick/prospect/player.
If Asset #1 is great, Asset #2 and #3 will probably only be okay. If Asset # 2 is also good, than Asset #3 will be bad. If Asset #1 is only good, Asset # 2 will also be good, and Asset #3 will not be bad.
The Carter: Great (Voracek), Good (a 1st), and Bad (3rd)
The Richards: Good (Schenn), Good (Simmonds), and Okay(2nd)
The Yashin: Great (Top2 pick), Good (Chara), and Bad (Muckalt)
The Seguin: Good (Eriksson), Good (Morrow), and Okay (Smith)
The Duchene: Good (1st), Good (Bowers), and Okay (Turris + Hammond Dump)
The Karlsson: Good (Norris), Good (1st+conditional), and Good (Tierney/Demelo)
The Kessel: + 2nd: Good (Kapanen), Good (1st), and Okay (3rd)
The ROR: Good (1st), Okay (Thompson), Okay (2nd) and Okay (Berglund/Sobotka)
The Burns + 2nd: Good (Setoguchi), Good (Coyle), and Good (1st) (I think this is the best Buffalo can hope for. Include a pick and get three good assets)
There are some outliers. Subban went for Weber, Hall went for Larsson, and Jones went for Johansson. Maybe there is another disgruntled star out there for a 1 for 1.