Gretzky is a tier above everyone, and Lemieux is a tier ahead of everyone except for Gretzky, Gordie Howe and Bobby Orr.
The rest of the discussion is a bit muddy to me. Are Jagr, Sakic, Forsberg, Bure, Yzerman, Lindros all in the same tier? I don't think so. Not at all. Their peak play may have been comparable to one another, but can we honestly put guys with shortened careers/peaks like Lindros, Bure and Forsberg in the same tier as guys who had full careers as superstars like Jagr, Sakic and Yzerman (just noticed you didn't include Yzerman, but I think he fits alongside Sakic and Jagr here). I don't think so. Using only the players mentioned, the "tiers" for greatness go like this.
- Gretzky
- Lemieux
- significant gap
- Jagr, Sakic, Yzerman, Crosby (in no particular order)
- even larger significant gap
- Bure, Lindros, Forsberg
Shuffle it slightly if we are talking peak play only (Lindros, Bure and Forsberg might move up, Sid might move down as he was injured for much of his "peak").