Very nice!
What are you guys doing to level out the playfield first?
I'm debating on using a drop of bondo, but I've also had good results with filling stuff like this with CA glue. My sanctum divot is quite deep.
Both options would need to be block sanded flat before applying the sticker, but I could easily mask around the area with a few layers of painters tape so I don't scuff up the good parts of the playfield.