I am interpreting “don’t particularly favor” as not particularly significant nor important for me personally nor in general.

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  • explaining, in subjective wording, why I prefer it differently
  • adding a change suggestion that may or may not be applied to demonstrate it
  • a personal conclusion and assessment, how important or significant it is to me, and what’s fine by me even if not my preference; e.g. “pick what you prefer or want” or “consider change effort”/“fine for now” or whatever

I feel like “sending back to the owner” sounds too strong; although it practically is that, it is not about sending it back; I share my opinion and view, and let the owner decide at their discretion

Whether I suggest a guideline depends on what it is; whether consistency and conformance would be useful in such a case, not for personal, subjective preference, but for code consistency or because they end up preferring my suggestion too.