The exoteric rites aren't important. The ToZ focuses on the inner, initiatory, esoteric knowledge of the ancient religions, rather than their exoteric aspects. That's what is most important. Many exoteric rites were just allegories for the initiates anyway.
As long as you don't blaspheme the Gods and you don't put anyone in danger, including yourself, then I don't see a problem with them. But for them to be considered official, they will have to be approved by Clergy.