The solution to these types of complaints like OP's is clear -- it's time to add "Sentimental" to Universal, Signature Series, Restored, and Qualified. Complete with the brand new pink label.
All books submitted to this tier will be automatically graded a Sentimental 9.8 so long as the submitter demonstrates, based upon preponderance of the evidence, that they truly believe the book(s) submitted have been kept in absolutely 100% pristine condition since their childhood. Spine tics, creases, fingerprint smudges, tears, spine rolls, etc. as well as any prior track record of grading prowess need not apply.
Malcontents satiated, grading complaints minimized.