I've tried both types of slicks and all the drag radials I know of don't work well on marginal tracks, none of them
On your deal with the water, rain, and low amount of runs on the track after the rain I would have put the bias ply tires on went for
The radials on my old car where usually from .1 to .18 quicker and from 1 to 2 MPH faster on the good tracks on my old car