with the new feature of becoming a witch i was more than exited to try it and my favourite is the spectral cat, but i don't like how my spectral cat's personality turned out to be, is there a way to change their personality?

I think it may reflect the karma of the cat, so having an evil familiar will have poor personality, as well as the owners taken into account as well. I may be wrong though.

hmm well my sim was a neutral mage when she was transformed, studied neutral magic then light, but the cat was summoned after she studied light magic
her traits are lazy,friendly,aggressive,pigpen, intelligence is average