Are those photos from the actual unit you’re reporting about? The indicators on the knobs seem pretty normal to me, they aren’t perfect but I’ve had newly bought ehx pedals with those little inconsistencies in the finish/knob indicators, seems pretty normal to me. The marks on the side are clearly from mechanic abrasion, tightening that input because it got loose or something like that. Might happen sooner than expected also, doesn’t necessarily mean the pedal was ‘abused’. It was well used but certainly doesn’t look like it was kicked around.

I’d say the gain thing is also the way it’s supposed to be. Do you have something to compare it to? Try searching on youtube for some video review and see if they explore the setting enough for you to compare to your experience and see if the pedal is actually defective or if that’s normal operation.