Normal? Changing pregain doesn't affect height in faders?

Maybe you are confusing things by using the term pre fader when this option doesn’t exist in Cubase.
The input gain will affect the meter in both “Post Fader” & “Post Panner” settings.

It will not make any difference when metering is set to “Input”

Oh, dear, it’s going to be a tougher transition from C6.5 than I thought

It’s exactly the same