I have always given fish oil & vitamin E, and have continued doing so even after I switched to raw (Sako is my only one that is still on kibble). I give Piper a probiotic too, but I had started that before I switched her to raw due to her stomach issues, and figured it couldn't hurt to keep her on it. Not sure if I'll continue it once it's gone though.
I do worry that they aren't get enough "stuff" though.. although I do feed a good variety. Wilson is still eating just chicken, since I just switched him last weekend. But Piper gets quarters, turkey necks, beef, pork, eggs, and now that I just got a ton of venison for free, that too. I don't feed any grass fed meat though.. too expensive!