As of now, these are the advantages.

1. Offload the work to another service.

2. Automatic retry in case of failed builds.

3. Get rid of Dockerhub's rate limit on pulls by using ECR(though ECR will also have a nominal charge if you are beyond the free tier and you can push to ECR yourself).

Beyond that, I am not really sure. I mostly just built it as a weekend project to see if anyone else would have use cases for it.