I have an account with iDrive - https://www.idrive.com/
Their pricing model is great and they now have 5TB for 6.95$ for a whole year
They do have sync client for Windows and scripts for use with Linux
And most importantly they have API.
Unfortunately not supported by Rclone. Could this be interesting to integrate?
welcome to the forum,
idrive is only $6.95 for the first year, then the price goes up to $69.50.
with idrive, you have to read the fine print very carefully.
"The 90% offer is applicable for the first year only. 90% offer is valid only if you are currently using a paid competing cloud backup service. You need to provide proof of your existing paid service provider’s account. Competing services include Carbonite, Mozy, CrashPlan, Backblaze, SOS Online Backup, Dropbox and Google Backup and Sync."
Yes, I know it is just for one year, I don't mind changing cloud provider.
I already ordered from then and got one year without providing evidence, and 70 bucks for a year normal price is fine.
Anyway, service is good and speed is fine, uploading at maximum speed from my ISP 100mbit
Also app for phone saves images, SMS, contacts etc.
Rclone support would be a complete solution 
sounds interesting.
i just signed up for a free 5GB plan.