Nice Read, Thanks Geshan Manandhar for posting. I agree with all that you have mentioned.
Another point I would like to add,
A clear sense of ownership of the PR. Who's responsibility to get it to the closure(Approved and Merged)? I have seen an issue(in Jira or Bigzilla) is not closed just because the associated PR has not been reviewed for long. Why? Because the reviewer is busy or the PR creator is not asking for it etc. Specially in a larger team, the practice of getting the PR approved and merged on time may have these hurdles as well.