I would love to be able to comment on channels, rather than only on individual blocks. I think having a comment section on channels might also be helpful for seeing what ideas or thoughts people have about them. I can also understand why you may not want to do this because it could lead to additional visual clutter, but this section could also be initially hidden!
I just discovered this platform a few days ago and it's exactly the thing that i've been looking for on the internet. Truly truly magical. I appreciate all that your team does <3 \(^.^)/