The more RadonSeal I apply, the better?
No. Over-spraying should be normally avoided. For the tightest possible seal, particularly against water vapor coming through concrete floors, you can apply additional light applications as long as the concrete absorbs the sealer. If you over-apply or let the sealer run and puddle, it will seal the pores in the concrete’s surface and give it a hard, glassy or whitish finish. Such surface is unpaintable, unless sanded first.
