Thanks all, especially Dan, Scott, and Dabac. I'll re-do the front wheels with the spokes projecting inward then, (heads out, as in the photo above.) Am using the Park tensiometer and will keep an eye on the spoke tension.
The rear wheels are 32, two-cross, since they're flip-flop track hubs with fixed on both sides. The spokes are Sapim CXRays, so I'm using a holder to avoid spoke twist. These will be ridden on a big 333-meter outdoor asphalt track which is being resurfaced right now, so they should be plenty strong.
I built up a set of 32, 2x road wheels about 10 years ago, and did a careful job of balancing tension and the wheels have endured 10 years of rough roads and heavy loads with only one minor retruing (or maybe not, can't remember.)
I knew Jobst mentioned radial lacing, but couldn't find that quote Scott posted. Very much appreciated, thanks!