Pushing a Heavy object - Right foot forward
2-foot jump plant - LR
Kick - Left leg
Starting sprint stance - Right leg forward
1 foot jumping leg - Right leg
All the bolded stuff suggests you should jump RL. Let me ask you something else: what way do you stand on a skateboard? Although I don't have a skate or use one, when I fooled around with one I was beyond any doubt standing on it in a LR stance, with the left leg on it and the right leg pushing into the ground. That's solid with my natural LR plant.
And yet, my RL jumping is like a French person trying to throw a baseball. Clumsy and uncoordinated and 50% of the time the ball goes straight into the ground. Seriously, half the time I try to jump RL, I end up either planting with my left foot anyway, despite my best intentions, or doing a horrifically awkward simultaneous plant. It's embarrassing. Same goes for trying to jump of my left foot, when I try single-leg jumps. Half the time I end up jumping off my right foot anway.
My right leg is superior in strength movements, btw, and it's bigger than the left. The last time I got a massage, the therapist made a comment immediately about how much more defined my right leg is than my left.
I'm the same as you on a skateboard. Normal stance.