Should I write a peer-review in third person? While it is generally accepted to write papers using the collective we, what is a common practice for writing peer-reviews: I, this reviewer, or something else?
For example,

This reviewer has a minor concern with how pink elephants are defined in this paper. It would have been helpful if authors defined an elephant first, and then added the color pink.


I have a minor concern with how pink elephants are described in this paper. My recommendation is to define an elephant first, and then add the color pink.
I recommend the first person.  Like most good linguistic constructions, the reader passes over it without explicitly noticing it, whereas your first construction with &quot;this reviewer&quot; holds up the entire mental process for a split second.
The idea of using the third person to &quot;soften&quot; the criticism: well, Paul Garrett knows how much I esteem him, and we usually see eye-to-eye on things.  But this time I simply disagree.  The reviewer is empowered -- nay, enjoined -- to supply an opinion on the work.  If you want to shade your opinion, explain very carefully and explicitly why you are doing that.  Switching to the third person should not convey that you are less sure of yourself, and it does not convey that to my ear.
[Imagine my answer began with &quot;This academic&quot;.  Wouldn't that have been more distracting?]