First AGP, questions on leveling and pad

Installing my first AGP, a 24' round. Base is currently compacted gravel (huge project to create a massive retaining wall in a very hilly back yard) which I will be covering with 3 inches of mason sand and leveling. I was planning to get a Gorilla Floor Pad to go over the sand. Does that seems to be a sufficient base plan?

Additionally, any specific tips and tricks on the leveling of sand are appreciated!

Thanks in advance!