Don't forget skill and vision.
That's okay, he was stronger than Lockyer and faster than Johns which puts him back ahead of them. Strength and speed are more important to a rugby league player than leadership.
It's also fairly hard to judge what kind of 'leader' he was given the squads he played with....
Seemed to 'lead' NSW alright in Origin (and the young Eels squad) last season. I'm not convinced leadership has anything to do with how one talks to the referees, and everything to do with how one acts on field, and directs teammates on field.
Again, have a look at Origin, whenever NSW were busted, Hayne would put up his hand for a simple hitup - and often make 10+ meters. He did the same for the Eels, when down and under pressure, he'd take a simple run from dummy half, or one off the ruck, and invariably make meterage.
Very hard for a fullback to show 'linespeed' and therefore defensive leadership, but he never shirked the kick chase, and would often try a huge kick himself followed by an attempt at an inspirational tackle to lift his team.
No clue on what they say on the field, but the Eels win% with him playing fullback vs not playing is staggering. And the defensive record with him at FB vs him not playing is also telling.
Lockyer is regarded as a great 'leader' on the field (and rightly so) - but he's known as such for all the years he played at 5/8. Funnily enough he converted to 5/8 in the season he turned 27. Not well known for his leadership prior.
I can't think of many fullbacks that you sit back and think 'yeah, great leader'. So I'm not saying Hayne IS one of the greats in that regard, but I don't know how much more he could do and still play his position - and wonder if that should be held against him?