The way I’ve been drafting it on Enoch, which is based on this draft, is lvl1 can be painted on lvl2 engraved but can be paint and then lvl 3 is engraved and “gold coloured leaf”. Doesn’t have to be actual gold, but leaf does look very different to paint so I think is a valid step up for the top level. This applies to cracks and patches.
Once cleared if you need to make repairs then how you handle that is going to be based on personal choice, what you have to hand, time and cost considerations.
All still open to discussion, but that needs to start with something.