Looks great. Very impressed with the vision (although language could be improved), and the "wont implement" decisions made. I would provide a bit of challenge

Looks great. Very impressed with the vision (although language could be improved), and the "wont implement" decisions made. I would provide a bit of challenge on tenet 2 however. Supporting "storage_class" for S3 is a compromise that clearly has to be made, and yet, it appears you're not realizing you'll have to make other compromises like it in the future. I would suggest a storage-specific configuration class for each storage backend, and then you wont need to make these arbitrary concessions. The power of OpenDAL will be its standardized data API, not its simplified configuration. I'm also not convinced that the project should implement OpenDAL Gateway. I cannot see how it will provide anyone any value other than making things more confusing.