Just curious. What is your shooting style? You sound like a video shooter touting good 4K, but then say 20MP is not enough. It's enough for 4K, which is why I think it was the chosen sensor size. Guess it means you shoot photos if you need the increased resolution. Would you consider having an R for stills which has 30.3MP and the R6 for video? Budget, or the need to carry only 1 body are valid reasons.The R6 only being 20mp is so frustrating. I have been waiting nearly 8 years for a meaningful 6D upgrade and even in 2020, it looks unlikely. For an 3-4 year difference I would expect increased dynamic range, higher resolution, IBIS and good quality 4K video. Finally 8 years on Canon achieve most of it but 20mp isn't enough. I guess Canon spec a $2000 camera just short of what's expected in order to force buyers into buying their $4000 that "has it all".
Many can make do with 20MP for photos, but I understand if the workflow involves large format printing or heavy cropping why it wouldn't be enough.