Paul,
Great write up of the technical steps! I did something similar and used Hugo to generate pages based on mark up and deployed to S3 via a Github / Travis CI build process.
For me, figuring out (and tweaking) the Hugo template system was the most challenging aspect. As a cloud platform I find AWS fairly straight forward, and the integration with 3rd parties like Travis are remarkably easy. Also you can't beat the free AWS Certificate Manager certs, especially now that Chrome wants everything to be HTTPS.