Best time I ever had was when I played the "All Montreal Canadiens" team several years back when the game honoured the franchise on their 100th anniversary. Lafleur, Beliveau, Richard, Harvey, Plante, Dryden, etc. That was also the only time I won the Stanley Cup playing that game, lol.
My wish would be that they allowed full seasons for specific eras: Have a 1954-55 season, so Richard, Beliveau, Howe, Lindsay, etc. could play against each other. Have a 1971-72 season so you can have the six new expansion teams (well, eight expansion teams since Vancouver and Buffalo came in '71), Orr, Esposito, Hull, etc. Then have a 1979-80 season so you can have the Islander dynasty, Gretzky, Lafleur, Lukowich (lol), etc. Then the 1989 season for Lemieux, Brett Hull, L.A. Gretzky, Roy... you see where I'm going with this.