For me, I am new to Boxcryptor and the reason I am trying to make it work for me is to access my files from my phone.
Anyway, I put all files on a hardware encrypted HDD and another version on the cloud encrypted by Rclone. I also setup a cloud synchronization service which syncs the content from one cloud to another. hence at anytime, I have 3 copies at 3 different location.
Ransomware is not a problem as you can easily detect it by monitor the amount of changes synchronized between accounts.