There is another possibility that may work for you since you just want more SSD space without using it as a second drive. You may want to try extending your current SSD into an NTFS folder on another physical SSD-- quick format NTFS your new SSD, lets call it D , and create an empty folder on that partition called something like C_Drive as the folder name. (Note that you cannot directly extend a drive into another physical drive, which is why you have to do it as a mounted folder.)
Then go into disk management, right click on the C drive, select change drive letters and paths, click on the add button, and then in the "Mount in the following empty NTFS folder" type the folder path in the box (so using the example drive letter above -- it would be D:\C_Drive), then click on OK.
This should add all the empty space on the D partition (new SSD drive) to the C drive space if you don't store anything else on that partition directly.
With this approach you just get more storage space and do not need to reinstall anything or rely on RAID for anything.