Best practice is to use the SSD for the OS mostly and data on the HDD. Have you considered moving the OneDrive (or other cloud storage) local folders to the HDD? 
Hi All I have a one year old Inspiron 5490 AIO that has a 256GB SSD and 1TB HDD drive. I'm running W10 Home latest version. I don't know if this is the standard configuration but the factory setting is for the OS, data etc to be saved on the SSD (C: drive) and nothing on the HDD (D: drive)  which means that my SSD is now almost full (211GB used) and the HDD is empty (131 MB used). I want to avoid future problems by re-organising these drives now but I'm not sure what the best configuration from the point of view of performance and ease of use is. I'm not interested in mirroring or other configurations as it's only personal use and most of my data is one OneDrive anyway. I particularly want to avoid splitting data or programs across drives so that it is a clean and simple setup. Does Dell or MS have a 'standard' recommended configuration or does anyone have  a recommendation? I'm reasonable competent to happy to bulk move data from one drive to another, as long as I know what I'm trying to achieve and that I'm not creating a problem for myself. Thanks Steve
How to configure SSD and HDD for best performance