When constructing a RAID 0 concatenation, distribute slices across different controllers and disks. Cross-controller and -disk slice distribution can help balance the overall I/O load.
Set the stripe's interlace value correctly.
The more physical disks in a striped metadevice, the greater the I/O performance. (The MTBF, however, will be reduced, so consider creating a RAID 1 (mirrored) volume on RAID 0 (striped) volumes.)
Do not mix differently sized slices in the RAID 0 volume. A RAID 0 volume's size is limited by its smallest slice.