1 - I know the landing profile called from the descent engine to shut down at 1.8m (6’) from the surface, did that happen on every mission?

Armstrong didn't because he didn't hear Aldrin call out the contact light and so he didn't shut down the engine until he saw it himself. This meant the struts didn't compress fully and they had to see if they could jump back up to the first rung.

Some of the astronauts confided later that they were going to let the contact light stay lit for a second or so before killing the engine. There's something in pilot's nature about not wanting to shut down a perfectly good engine while still above the "runway". But they said they followed the profile in the simulators.

On a couple of missions you can see a jolt in the 16mm DAC footage as they drop the full planned distance.

2 – I agree with the reason that the pool of light behind Aldren in AS11-40-5902 and 5903 is reflection from the LM aft equipment bay.

What I can’t figure out is why are the MET tracks from Apollo 14 so bright

Because the soil has been artificially compacted and so forms a semblance of a uniform flat surface without much texture.

Remember that if you look anywhere but directly down-sun you're seeing a mix if lit and shaded sides of the texture. If the texture is mashed flat there's less shadow to see.