I do think Bergeron will be in this discussion eventually. No one has really defined the Bruins like he has in the 2000s, and the Bruins have had a good deal of success in that span.
I'll just get it over with...
Eriksson.Smith,Fraser,Morrow
Pre-Expansion: Shore, Schmidt, Orr and Bucyk
Post-Expansion: Bourque, Bergeron Chara and Thomas
Expansion was in 1967. Orr and Bucyk both played the majority of their B's careers post-expansion.
I like three of your four "post" guys, but I would not include Thomas. If I was forced to put a goalie in there, it would probably be Cheevers.
On second thought yes Cheevers would be the better choice. It is just that Thomas had such a magical run that Cup season and was such a great story, so he really stands out in my mind.
Orr & Bucyk started their careers before 1967 that's why I included them there.
I do think Bergeron will be in this discussion eventually. No one has really defined the Bruins like he has in the 2000s, and the Bruins have had a good deal of success in that span.
Sinden
Orr
Bourque
Schmidt
Given the town's reputation (perceived or not) and outside the box :
Lydon Byers
Jay Miller
Wensink
Jonathan
Honorable Mention: Nilan