I do full length movies, for independent festival as Sundance, Toronto, NY Film Festivals and you can send your footage, even at 720 x 480. For good quality it's enough sent at 1280 x 720. So you can crop from 1920x1080.
(I saw material did it with h264 too).
The only advantages today with 4K it's the crop, a little of digital panning, and nothing else. But... If your focus are perfect.
For a perfect focus, very sharp image, you need a very good lens like Canon L or Zeiss compact Prime.
Why think to get 4K? More than this, your skill filming and directing could be more important than RAW or H264.
4k It's a marketing invention. Believe me. I'm on the wild side. Shooting and shooting al the f... day. with a 5D ML.
Enjoy!