I thought about pre-defined reject reasons for suggested edits, and here are two I think might be helpful:
Edit changes code of question
As discussed in this meta post, editing the code of a question is not recommended. But right now, there does not exist a pre-defined reject reason for this rule. I think it would be good to have it for
- new people who maybe don't know that this would be a valid reject reason
- people who do not want to write a custom reject reason each time
Edit is too minor [for an old question]
It seems that the general consensus in this question about minor edits is that there are at least some circumstances in which an edit might be considered too minor to approve. If that turns out to be the case, a pre-defined reject reason for this case might be helpful.