
Humm, I tried last weekend what you said about the ways of paddling straight or with an angle and honestly, it was impossible to realize what I was doing on the water. It looks like I really can't control in what direction I paddle. It is like trying to control how you breathe. You just do it intuitively.
A nice trick to easily control the paddle direction is just trying to move your top hand as far as possible overboard, (if your top hand is the left one like on the pic, move it as far right, even 1'+ off the right rail). This way the blade will do a natural "C" stroke, paddle pivoting around your lower hand. Try it, and exaggerate at first to feel how it works. You should be able to get negative row easily.
Horses for courses. Let me take the dissenting view, I'm an outlier at 6'2 & around 125 kg, smaller blades don't do it for me in surf...not enough grunt to overcome lardy inertia and get some quick board speed up. For surf and DW it's Ke Nalu Molokai for me, it's big but not huge.
I agree. Lardy SUP and using QB 110.