Road Wheels & Road Wheel Recommendations?

Why so down on plain gauge spokes?

Because they are evil too stiff. If the spokes are too stiff, they concentrate loads in just a few spokes. If the spoke stretches a bit, the rim moves and because the rim is stiff and doesn't bend much, it ends up pulling on more of the adjacent spokes so the load is spread over a greater number of spokes. This is why butted spokes generally suffer from fewer fatigue failures than plain gauge ones - for the same peak loading on the rim, the peak loading on each individual spoke is less.