Well first of all, you're trying to record in CBR. That isn't always going to be the best for quality and space on your hard drive.
If you still want to use CBR, 10,000 is WAY too low of a bitrate to be recording 1080p60fps with NVENC. Use atleast 50,000.
But if you want good quality, use CQP (Constant Quality) compared to CBR (Constant Bitrate)
Then you just adjust the QP levels based on how big you want the files to be. 26 Being the smallest files but the least quality and 1 being best quality but biggest files.
Most people use a QP of 16.
EDIT:
@koala we posted at same time yikes xc
EDIT #2: To go into what Koala said, youtube compresses the sh*t out of their videos. You're never going to get perfect quality on videos uploaded to YT.
(BTW, when you upload a vid to YT it quickly encodes it in a very fast but very inefficient encoder, and will later on re-encode it in the better, slower one. However, it prioritizes videos that will be popular and need to have the better quality one first. So, the bigger your channel, the better the quality on your videos. [FYI videos posted as unlisted or private get sent to the bottom of the queue so they almost never get re-encoded])
