I used the straight edge after the guitar had been left unstrung for several months, so that might acount for the lack of 'relief'.
It is steel strung, I do use lighweight strings, and change them regularly as modern strings go dead a lot faster than those I used to get from the GDR years ago.
The plastic strip is the end of the strings vibration, it is still high enough to suport the string for all the chords I use.
I know the maths of sound but not really how it applies to music, just the relationship between frequency and the physical body producing it. Perhaps if I take a look around on the 'net I will be able to see if there is someting dreadful going wrong or if it just the natural nature of wood and wire not conforming to the imutability of silicon and electrons.
The Framus is an old friend, I bought it for £25 about 35 years ago so I can't complain about the durability of the instrument, but I would be lost without it.
I have tried out various instruments over the years, and found one last year which sounded right and I could get my hand around the neck - but it was just under £1100. I tried another one one by the same maker same size and shape and it sounded dead, so even at that price the voice can be either good or bad.