I'm a developer myself and I'm currently looking for new projects to work on. I'm interested in hearing about your idea if you don't mind sharing it. You can email me at [email protected]
I'm actually using Wasabi as my cloud storage backend for File Ark (https://fileark.launchaco.com/), which is an app I made to interface with it.
It's definitely cheaper for archiving files, but there are some catches like minimum file size and storage duration costs, but still overall cheaper than the other storage solutions I've come across.
I completely agree that data loss is a huge issue. Cloud storage usually comes with pretty high redundancy, but if you're using a service you don't know much about, it's definitely safer to keep your own copy of the file.
A use case I had was that my Mac was running out of hard disk space and I didn't want to carry around an external hard drive or get a new Mac, just for more disk space. I tried cleaning out as much unused applications and files as I could, but there still remained large and old files that I wanted to preserve to keep a record of them.
Moving it to cloud storage for archival gets me the long-term storage and by deleting the local copies of it, I was able to get back a good chunk of space on my Mac. Not everyone may have this use case, but it was one I came across where deleting the local copy made sense.
It's not a backup solution, but rather an archive. With backups, you might expect files to be synced after changes, which my app won't do. Rather as an archive, you can just drag n' drop the files/folders you want to archive and it'll be moved to cloud storage and then you can delete the local copy of those files on your computer.
The files in this archive storage are also not meant to be shared like Dropbox or Google Drive because it's supposed to be your personal archive of files/folders, so there's no sharing functionality.
If that fits you what you are looking for, do give it a try.