The two best all-round hockey players of all time (offense, defense and physical play) have to be Howe and Orr. Howe dominated for over two decades while Orr lasted less than a decade.
Orr and Howe could change a game not just with their offensive skills but also their defense and physical play (including fights).
No one challenged Howe for years until Lou Fontinato of the Rangers began to beleive his NY press clippings as the NHL's toughest player - big mistake as Howe rearraged his facial features and put hm in hospital. Orr was also very good with his fists.
In his prime Howe would be triple shifted and is reported to have played 50 minutes in some games. After he retired he was tested and his oxygen uptake and recovery time was found to be incredible. A brief rest on the bench and he was good to go for another couple of minutes.
If you have ever seen video of Howe coming down the wrong wing, powering past his check and switching hands on his stick to get a better angle
Depending upon how you weight your criteria for the greatest player of all-time it will be Howe, Orr and Gretzky in a pick 'em.