I would suggest looking into Grip-tex, the rubber non skid additive that is meant for use with Awl-grip rather than sand. In my experience sand is difficult to apply evenly and when the paint inevitably wears away the sand is visible, leaving a "dirty looking" deck.
This stuff is available in several "grits", we used a 50/50 mixture of medium and fine. Though not the best nonskid of all time (esp right after painting) it wore into a decent finish that looked great for its uniformity. We did spray it with an inexpensive LPHV gun (the type with a blower drive rather than compressed air- made by Fuji) and a large bore nozzle. A couple of ball bearings in the paintcan helped to stir things up and keep the spray uniform.
We did use the Awlgrip primer first, though, PaulK is right about the concern that after all that effort the new coating separates because of a shortcut.
Whatever grip you add to the primer will be degraded when you paint over it, as the paint will make things less "non-skid".
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"