I'm never particularly sure what to do when somebody suggests a good edit but that can be improved.
Say you suggest an edit. You fixed formatting, you fixed grammar and improved the overall quality of the post.
I as a reviewer, see this edit but see some minor areas where it can be improved. In the past I've "improved" the edit, but then realised that I just hijacked their edit and put my name on it and didn't give them rep.
This isn't fair, the editor deserved their rep, they made the greatest contribution to the edit.
In these cases what should I do? Should I approve the edit, and then add in my own edit after theirs? If I'm jumping through a review queue that would mean I would have to save the post and keep checking back for when the edit gets accepted to add my own edit.