On Morcambe bay in Lancs ther are not alot of things described above and so you are more than legal to fly at whatever height you like
Someone I know flies very low over Morcambe Bay from time to time, and claims to be able to see several cars stranded (presumably abandoned many years ago) in the quicksand. I wonder if these count as "vehicles" for the purpose of the 500' rule???
As for PFLs, I like to think of the PFL as being a way to practice the forced landing up to, and maybe slightly past, the turn to final if there are issues with the 500' rule. The latter stages of the PFL, including the landing, can be practiced at an airfield by doing a glide approach.
FFF
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