You could do it by career over 15-20 years periods. Most true top stars play at least 15 years, if not 20. The better the player the longer the star hangs around. You could include ALL of a player's career (including junior, WHA and Europe) to git in which 20 year period they belong in. I ONLY include the player's that are in fact contained most completely within that time frame... Only Gordie Howe truly has a 25 year run as opposed to 20 years. Only trying post WWII as hardly any players had 15-20 year careers before then. Right now I was just quickly trying to get the players for each era or generation. Sometimes is is hard to pick where to put them with overlap. Kelly was among the best defencemen by 1949... but played after 1965... I put him in the 1945-65 category. Hasek is in for 1985 even though it predates his NHL career by the entire first 5 years.... as he was the best goalie in Europe or outside the NHL almost certainly from 1985-1990 and that surpasses him hanging around (still at a high level) in the NHL after 2005 IMO. I don't know enough about the top Soviet players to put them in the correct time period... But Fetisov is likely 1975-1995. I am sure I am missing many players as this was just a quick list to get started and no order was intended from below. However it seems to me that grouping players this way really does show the eras or generations of players. Who were the best players that started their careers in each half decade. Only true dominance counts outside of the NHL IMO... Junior can matter if you are absolutely dominant... like Lafleur or Potvin or Orr... it really adds to your resume if you don't have quite 20 full seasons in the NHL. It could be interesting to select the best 10 players of each generation. I would guess that there would be few in the top 10 for each 5 year period that were no in the HHOF.
1995-2012 Brodeur, Lidstrom
1990-2010 Jagr, Sakic, Forsberg, Lindros, Belfour
1985-2005 Mario, Hasek, Roy, Chelios, Yzerman, MacInnis
1980-2000 Gretzky, Bourque, Messier, Hawerchuk, D. Savard, R. Francis
1975-1995 Trottier, Bossy, Statsny
1970-1990 Dionne, Lafleur, Clarke, Robinson, Potvin, Perreault
1965-1985 Orr, P. Esposito, Park, Parent
1960-1980 Mikita, Keon, Ratelle
1955-1975 B. Hull, H. Richard, Mahovlich, Plante, Glenn Hall, Bucyk
1950-1970 Howe, Beliveau, Sawchuk
1945-1965 Howe, Lindsay, Harvey, Kelly
1940-1960 R. Richard, Lach
1935-1955 S. Abel, R. Conacher, Apps, Broda, Brimsek, Blake
Clearly I did not go through nearly all the player's that should be included. Maybe someone is interested in adding more player's?