I can't claim to have seen Richard play, but what differentiates him from Ovi at this point seems to be playoff goalscoring and point finishes. Richard has 7 top 3 finishes, and Ovi 5 such but he actually won the trophy as well, with great competition, which Richard never did.
Sorry, what "trophy" are you referring to here?
Ovi is clearly a better RS goalscorer with 8 Richard wins to 5 (yeah, I know the award is named after him lol...).
I agree that Ovechkin should rank higher than Richard overall (see my detailed post in the "greatest goal-scorer of all time" thread), but I wouldn't say it's "clearly" better; more like, a bit better:
Ovechkin (best 12)
1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 4, 5
Richard (best 12)
1, 1, 1, 1, 1, 2, 2, 2, 3, 4, 4, 5
The three times Richard was in 2nd place, he lost out to (i) peak Gordie Howe (by 1 goal), (ii) peak Jean Beliveau, and (iii) prime Gordie Howe.
A lot of people have both Howe and Beliveau in the top-6 or 7 players of all time, and those are the guy preventing Rocket from having 8 goals' titles, just as Ovechkin has.
And Rocket was better in the playoffs.
