GFX 100S vs 100 S II

I am looking to move from Canon FF DSLR to GFX platform.

I mostly shoot landscape, astrophotos, and few family events. My question is AF on 100S, wondering if AF on 100S will be fast enough to shoot indoor shots of people interacting, not sports or studio setting. If not is 100S II AF more accurate and faster?

As for lenses I am considering GF 23 f/4 or GF 20-35 f/4. Is the distortion on 20-35 more pronounced than the prime and is the IQ about same?
What lens would you recommend for mid?

Thanks much!