I love AWS and for any startup that I expected to need to scale quickly I would choose it in a heartbeat.

However when it comes to low-traffic side projects and experiments where costs of a few hundred dollars matter, I prefer Linode or DigitalOcean with ansible provisioning and B2 for block storage. It will cost you more time for sure, but it will give you better performance at the low-end which means you can break even sooner. If it takes off you can always migrate to AWS, GCP or Azure later.