Ryder and Ferrence have no value/negative value due to cap hits and Thomas due to the contract is pretty low in terms of trade value.
The reason I like the trade for Boston is that I think next year they are a top 4 team in the east. Add a couple of solid pieces remove the cap liabilities and the B's have a shot 2-4 cup runs with this core. And the best part about it is that they give up one pick/prospect they still have a ton of picks and prospects in the system. Frees up enough room to sign all important RFA and UFA and add aback up goalie.
Can you imagine Boston icing a team like this:
Lucic Savard Hemsky
Penner Bergeron Wheeler
Strurm Krjeic Recchi
Paille Sobotka Begin
That line up has the potential to be crazy good.