I can certainly understand your concerns. I might be concerned, too.
It's certainly no guarantee that your next child will be on the Spectrum.
I wish this wasn't a crapshoot----but it sort of is.
It might be more difficult raising a child on the Spectrum----but it is possible that this child might be able to do great things owing to being on the Spectrum (certainly not ascribing "superpowers" to Spectrumites). Have you heard of, or read up on, Temple Grandin? She is not a stereotypical savant; she invented many useful items which, for one, provided a way to humanely vaccinate farm animals.
There is a slight sense that I might have been able to do "great things" had my mother left me alone, and "allowed" me to be autistic. I don't know, really. It was a rough childhood for me because my mother was frustrated, didn't want me to embarrass her, and there was no concept of autism having relatively positive traits back in the 1960s.