I was previously using Cloudflare in conjunction with a Linode server. The disadvantage of this, however, is that you need to ensure that one server never goes down otherwise anyone hitting a cold cache would see the site down.

Also, why do you need a server at all? If you are doing nothing but serving static files then why incur the overhead of maintaining LetsEncrypt certificates and writing Nginx config files? AWS provides a simple interface in which you can view and manage your static files without having to ssh into a server.

On the point of price, I'm predicting my total cost of hosting for a site serving roughly 40-45k users per month will be roughly $7/month. All whilst minimizing the amount of administration time required and monitoring of a more traditional system.

Hope this clarifies this, would be keen to hear any counter thoughts!