Crank BEFORE Pumping!!
OK, if I was living up north, I'd be using my primer solenoid more often, but down here where it's warm, a few throttle pumps is all it takes if the temps are below 70 degrees. But....and this is REALLY important, you can't tell someone to "pump the throttle, then crank"! This is a guaranteed way to make a pool of fuel in the FAB, and quite potentially hazardous.
If you're going to prime with the accelerator pump, you need to get the big suction pump (the engine) going to draw the sprayed fuel into the engine FIRST! Crank, THEN pump, and don't pump if you're not cranking! This is how the "old wives tale" about fires got started - because it is true, if you pump, then crank. If the engine is sucking while you pump, it draws the fuel right into the cylinders and makes fire where you want it.
OK, I've repeated myself enough - sorry. I'll just add that down here in the warm climes, I have used the electric primer solenoid once in 1,000 hours on the RV-8. Louise's -6 has no primer system at all (and it came from Oregon) - so yes, you can easily build without one. The disadvantage of a primer is leak potential - so if you build one, do it right with lots of strain relief and flex loops.
Paul