Using a mSata SSD to cache a SSD is pointless.
Raid0 - what ae you plannng on using that require the higher Sequencial performance.
Raid0 is primarily for inproving performance for accessing LARGE data/File structures such as editing large Jpeg/bitmap Photos often, editing/working with Large Video files (ie a dot VOB is typically 1 gig for a single file).
Raid0 does VERY little for loading an OS and drivers/files as these tend t be smally files that are randomly spread out on drive. Raid0 does NOT improve access time, and does very little for improving small 4K random performance.
NOTE wit raid0 you lose TRIM support UNless you have an Intel system that is using a Z7 series chipset/driver. For Intel Older systems there is a NON-supported work around for the Intel p/z6 series. Currently NO Trim support for AMD systems if using Raid.
I much prefer, with 2 SSDs, a OS/Program drive and the 2nd drive as a storage drive with Most access files on it.