Thanks Beau! I really appreciate the kind words.
I am a fan of your cover too!
I borrowed a color scheme from an 80s pulp sci fi novel, which really helped me.
I've always liked doing photo collage and now I have an excuse to do more of it. I used Canva for the whole cover. Free version. Remove.bg to remove the backgrounds of the public domain images.
Layout was a free Canva template:
https://explorers.itch.io/classic-starter-template
I used Affinity Designer and Adobe Fresco for the cartography. Fresco is free and amazing for those that have a tablet with a Pencil. I may do a quick demo on Bluesky.