Opinions on Sigma 16mm f/1.4?

I am using my GH5M2 with two zoom lenses, which are good for daylight and travel. Proving very enjoyable outdoors with the small size/weight.

For indoor/low light situations, when I need portrait focal length, I am planning to adapt my Nikon 35, 50 and 85mm f/1.8 primes. I don't need those long focal lengths often and definitely not for fast moving subjects. So, I am not inclined to spend money on M43 primes.

For a wide normal, I need about 35mm FF FOV. I am also inclined towards faster aperture. Despite its size, the Sigma 16mm f/1.4 is appealing to me. It has the focal length I need; has fast aperture, and I like the price. If I have to reject this lens, that would be purely for the size.

Any recommendations with respect to this lens or anything else like this at F/1.4?

I do see some MF lenses that are about a third of this price, and half its size, but I am hesitating because I haven't used MF on digital cameras (last time on rangefinder camera in early 90s).

I use MF for video on FZ2500 for stage events where I pre-focus for desired depth of field. I can do it despite my less than perfect eyes because Focus Peaking helps a lot. I can probably manage with still subjects but may not be able to deal with the smallest movements like my cat's.

Thanks.