In my opinion the clock should stop as soon as the pilot enters the
cylinder. We shouldn't have pilots in the finish cylinder still
racing.


You haven't met enough contest pilots. If the rules change in this
way, pilots will aim to finish one mile out, 50 feet, 90 knots and
then float in to the landing, european-style.

If you don't think people racing inside the cylinder is a good idea,
then what you want is a "hard floor". 499 feet = distance points only.
Now, again, everybody inside 1 mile is done racing, but pilots aim for
500 feet, not for 50 feet.

John Cochrane