I have a few questions to you or anyone else who can comment on them.
How does R6 4k video filmed in PR 422, 10-bits compare to 5D3 RAW video filmed at 14/12-bits lossless in terms of image quality? Have you made such comparisons or have you seen them on the net?I working on a side by side test of this. But honestly, the 10bit on the R6 is pretty amazing. Of course RAW would be better, but it's still 10x better than regular h.264. I am used to grading ML footage in adobe camera raw so the workflows are drastically different. But it's way better to be able to edit the footage right out of camera.
And there is extremely good shadow recovery. I've been 4 stops under exposed and there is almost no noise when I bring the image back up to EV0. A huge one is that I can also adjust the white balance of the video in post pretty accurately with the little dropper tool and no quality degradation.
The R6 does not shoot in ProRes though. The R6 uses HEVC instead of Prores.
What do you mean by "better C-log"? Is the current one not good enough? I've used Clog1 Clog 2 and Clog3 in the past on other cameras. Clog3 better uses the full dynamic range of the sensor. Here is an extreme example taken on clog1 on the R6:

I've shot the sun and the ocean in clog1. Now obviously, the sun is going to be completely blown out regardless of what I film at. But in the clip, the highlights only go to about 80% of the highest color information. The shadows only go down to 10%. I call this "too flat" and this is an extreme example. Most of the time, the shadows and highlights are usually within 60% of each other in clog1. When using clog3, these numbers are spread a lot more on the spectrum. Shooting on the c300 mark 3 in clog3, there is NO POINT in shooting RAW via HDMI. Clog 3 is that powerful to me.
But I will say that it is good enough. I've actually never been able to manipulate footage to such quality so fast before.
How about the filmic look - doesn't R6 video look too digital? It depends on what you mean. When think of "Filmic" look, I think of imperfections. Maybe a little softness on lenses, or maybe random grain. High contrast. Good dynamic range. And stuff like that. But then when I see shows like Breaking Bad that was shot 100% on film, I feel like that is super digital looking with amazing dynamic range. But it was shot on film.
There are a lot of ways to make digital look like film, and film look like digital. The Alexa's and RED's are known for there dynamic range and ability to push to make look like film. But nowadays, that dynamic range exists on basic cams like these. The Sigma FP can produce some amazing footage that can be converted to look like film. I truly believe that with some tinkering, one could make the R6 look like film.
The biggest downside is that the R6 also films in IPB mode though and not ALL-I (which lowers the quality by compression). It's not too noticeable to me, but I'm sure there will be artifacts if I were inches away from an 80" screen.
Now that you have the R6, don't you miss ML RAW video? Actually not really (which is surprising me). I thought I would be switching back and forth between my 5D and the R6 on shoots, but you CANNOT beat the autofocus system on the R6. I was shooting a model on an EF 100mm f/2 lens and she was in moving around a lot. BUT SHE WAS IN FOCUS THE ENTIRE TIME! Every single frame, here eyes were sharp. The IBIS also was perfect for handholding 100mm. No matter how good Magic Lantern gets on the old cameras, it can't beat such features.
Of course being able to PLAYBACK the footage on set is also huge. The zebras are helpful too, just as helpful as the magic lantern zebras.
Personally, I think that the R6 will become the "perfect camera" if one day we see ML on it but this is just me and my dreams.Me too. I mean honestly if they can find a way to implement RAW HD on this camera then I would be happy (RAW 4K probably isn't possible due to slow SD card rates). But there is RAW light that can probably handle it. Of course I'm sure MLV can handle it too. I couldn't imagine what you devs could do with a 300MB/s write speed. It would be 100% the perfect camera if it had ALL-I recording with Clog3. Right now it's at about a 95% to me. But for being $2,500 plus a cheap $50 EF adapter (which works perfectly btw) it's basically perfect to me. I'm probably going to be using this camera for the next 10 years comfortably. I'm actually impressed with Canon's new battery too. It def lasts longer then the regular LP-E6 batteries. The new battery even works for my 5D!
TLDR: I would basically call the R6's clog1 9.5bit footage (Not full 10bit if that makes sense). More than double the dynamic range of regular h264, but still not using the camera's full capabilities. The autofocus and ibis are to die for though. I never realized how much I needed autofocus. I can properly look at the footage and see things that shouldn't be there instead of worrying about racking focus at the right time.
Edit: Something that I want to try is making a video in 20fps photo burst mode. The photos are 16bit (a bit overkill but sweet) but still 4fps too slow to make the smooth 24fps. Maybe I can shoot a music video and slow the song down to 0.83x, then interpret the footage as 24fps. Open gate (4:3), 5.4K, and 16bit! I can't imagine what that would look like.