Get 3 decks that fit snugly together and glue 2 of them into a thick deck.  Carve that one ornately and then glue it to the unmodified deck.  the result would be functional and ornate.

I'm sure I could program a CNC router to do the same thing. Back in the 80's I used to have a "hardbody" deck that was about 1 inch thick. It was like a cricket bat with wheels but was fast.