You write the most thought-provoking questions. Love it!
My practice is to not leave a critique unless a writer specifically asks for suggestions on how he or she might improve their writing. My stance is that everyone who submits poetry, stories, and articles to the HP readership is at different stages in their respective literary growth. So I usually try to leave them with something encouraging or at least relevant to the topic at hand.
That said, I know that each one of us writers needs to--every now and then--go back and proofread what we've written. I can't tell you how many times I've spotted an omitted word or phrase, or erred in my punctuation, or--upon a second or third reading--found a better way to say something.
I sincerely appreciate that you asked this question. Have a great week, and have fun with the tricksters tonight!