most newer pieces of video/image editing software will let your GPU do the heavy lifting, and its generally a heap faster than using even a 8 core 16 thread CPU. so i wouldn't totally throw away the idea of low/mid range gfx card
a 1660 is $400. not that much in the scheme of things.
i would also get a 1tb nvne drive for the boot drive
I do basic video editing rarely, Premier Elements doesn't support use of a GPU, so it'd be money largely wasted. My 2600K CPU is fine for video, so a 50% faster CPU would be good. I can always add a faster GPU later if I need one.
I don't keep data on my boot disk, to keep the Macrium Reflect image small, so a 1TB NVME drive isn't really going to help me unless I partition it - not sure if that's a good idea or not. Plus I already have good quality Samsung 960 Pro SATA drives, plenty of life left in them and what I do isn't I/O heavy, so I don't know if I'll even bother with NVME. If I do it'd probably be 256GB for OS, programs, swap. Might add NVME later, easiest thing to replace is the disk.
Not sure what I'd use instead of ReFS storage space mirror. Maybe just bare NTFS drives, with an internal backup nightly.