I am healthy bmi but have pcos (no cysts) and other autoimmune issues (alopecia universalis, psoriasis). are inflammatory/diet factors possible?

Probably now: Alopecia universalis is well-characterized as an autoimmune disease. I have an affected colleague who is an athlete and loves being hair-free. Psoriasis is a common illness with immune mechanisms while PCOS is almost certainly not immune. Diet isn't the key. Going you can and will stay physically fit -- aerobic exercise may help a great deal with your genetic heritage.