You can delete your Google Drive cache on a computer by clearing your browser history. On an Android, you can clear Google Drive's cache through the app's Settings ...
The main purpose to map a network drive is to enable access to files stored on another device connected to the same network. So, once your work is done, you can configure your system to remove cached ...
You can replace it with a larger mSATA SSD and use it as the system drive, too. At least that's how mSATA usually functions, and should function that way unless they did something weird to it to use ...