I completely agree with MissterDog and I also wanted to add one last point.
If you want to imitate nature (low night temps and all) then you should have no problems with using a CHE or other heat lamp. In the wild, the ground isn't warmed from below by an enormous heat mat. How is it warmed? By the sun.
The wild ball pythons aren't warmed early in the morning from below by some mysterious source, they're warmed from above by the biggest "CHE" in our solar system.
Sure, the sun heats the ground and then the snake can get belly heat, but the point is that the sun was the one to warm the soil, not some underground heating system.
Even if you ignore the fact that temp drops are unhealthy, I'm sure you can see why only using a UTH is not mimicking nature's heating system like you want to.