It's hard, though, to keep code reviews from turning into style and architecture reviews. Code reviewing for style is subjective. (And if someone on the team regularly produces very poor quality code, code review isn't the vehicle for fixing that.) Code reviewing for architecture is expensive; settle on a design before producing production-ready code.
My $0.02 from the other side of the manager/programmer fence.
"All changes are reviewed by a subject matter expert who verifies that the change meets the planned activity as described in the associated issue/ticket. Changes are not deployed to production environments until authorized by a subject matter expert after review. An independent reviewer evaluates changes for production impact before the change is deployed..."
If you are doing code review already, might as well leverage it here.
That's exactly right. After said process, it comes down to trusting your coworkers to execute capably. And if you don't think coworker is capable, say so (or if they're junior, more prudently hand them the simpler tasks — perhaps code review behind their back and let it go if the code is "valid" — even if it is not the Best Way™ in your opinion.)