Spatial can only carry CAU III. It depends on the pilot / the circumstance / and what its role is. I stomp gunboats in mine. If you feel like fighting forever, you can kill a cruiser with it. SNAC is good, and then drop on some codes.
For pirating, i prefer a Sabre over a spatial. Its a good, all around fighter and you can kit it out for solo pirating.
Want a challenge, fly a Spatial, you'll love it when you actually get used to your ships capabilities.
If you just don't want/can't/don't have the time to learn how to fly a Spatial, get another ship, you can do fine with them as long as you have played before.