I think I tried most of the options from
here (Comet Lake section) including yours.
My current video config is:
View attachment 474524
Sure, I would be glad for your feedback on that.
PS: I even used more complex video config from Casey (he uses framebuffer patches) - it works without modifications with the same result. You can even delete everything from his config except
AAPL,ig-platform-id
device-id
and it will still behave the same, the only pretty cool option is 'model' which is used to print out the graphics in About This Mac.