i would suggest keeping a large tire on the rear and a narrow on the front with about the same psi.
say 50(2") rear, 40(1.6") front.
the rear should be pressured tuning rolling resistance and comfort, the front should be pressured to ensure grip both dry/sand and wet.
i now have a 2" nobby on the rear (no budget for a proper road large tire) which is puncture resistant by virtue of the tread pattern (downside is less grip when wet but i can't be bothered, it's a rear tire, not a front) and a 1.6" dureme on the front which has good puncture resistance. it works very nicely.
sudden front punctures are more dangerous than rear punctures on the road and less psi with a large front tire affects both grip when wet and also is more puncture prone.
a bit offtopic... be sure to generously put talcum powder because it helps in multiple ways. mounting and dismounting is easily done, better grip because the tube won't stick to the tire, better rolling resistance, corrosion inhibitor, prevents flats because the tubes that do not stick to the tire are harder to penetrate by stuff that would eventually be going out of the tire,