Top 10 Points
Kane - 6x
Malkin 4x
Top 10 Goals
Kane - 4x
Malkin 3x
Top 10 Assists
Kane - 5x
Makin - 3x
Malkin does have one more Art Ross but Kane won his with a bigger margin. I'd say its dead even at worst but I have Kane higher due to his remaining a top player year in and year out where Malkin has lost a step.
A yearly comparison might be a better way of looking at it.
Year 1
Malkin - 33 G, 85 P
Kane - 21 G, 72 P
Year 2
Malkin - 47 G, 106 P
Kane - 25 G, 70 P
Year 3
Malkin - 35 G, 113 P
Kane - 30 G, 88 P
Year 4
Malkin - 28 G, 77 P (67 GP)
Kane - 27 G, 73 P (73 GP)
Year 5
Malkin - 15 G, 37 P (43 GP)
Kane - 23 G, 66 P
Year 6
Malkin - 50 G, 109 P
Kane - 23 G, 55 P (47 GP)
Year 7
Malkin - 9 G, 33 P (31 GP)
Kane - 29 G, 69 P (69 GP)
Year 8
Malkin - 23 G, 72 P (60 GP)
Kane - 27 G, 64 P (61 GP)
Year 9
Malkin - 28 G, 70 P (69 GP)
Kane - 46 G, 106 P
Year 10
Malkin - 27 G, 58 P (57 GP)
Kane - 34 G, 89 P
Year 11
Malkin - 33 G, 72 P (62 GP)
Kane - 27 G, 76 P
Year 12
Malkin - 42 G, 98 P
Kane - 44 G, 110 P
Year 13
Malkin - 21 G, 72 P (68 GP)
Kane - 33 G, 84 P (70 GP)
Year 14
Malkin - 25 G, 74 P (55 GP)
Kane - 13 G, 49 P (37 GP)
When comparing each of their respective years in the league, Malkin's been the better player more often. Some seasons are close in terms of points per game (year 5 and year 7) with Malkin missing more time, but there's only been 4 years where Kane was clearly the better player.