ND Filter for video

I need some help choosing ND filters for video. I've been researching this for a while, but I'm still undecided.

I'm using a Sony A6700 with a Tamron 17-70mm f/2.8. I shoot in 4K24 at 1/50 shutter speed and S-Log3, so my base ISO is 800. Because of that, I need ND filters for outdoor filming.

I'm leaning towards a fixed ND kit rather than a variable ND because I've read quite a few reviews about color shifts, reduced sharpness, and other issues with some VNDs.

Almost all VND filters seem to have a range of only ND2 to ND32 (1–5 stops), and I'm worried that won't be enough for bright daylight, especially when shooting at ISO 800.

As an alternative, I've been looking at fixed ND kits, but almost every kit only includes ND8, ND64, and ND1000. My concern is that ND1000 seems more useful for long-exposure photography than for video, while I might miss intermediate filters like ND16 or ND32.

My budget is around €150.

What would you recommend in that price range?

Do you think I'll ever need more than an ND64 (6 stops) for video with this setup?

Also, do fixed ND filter kits generally allow stacking, or does that depend on the manufacturer?

Thanks!