I've heard Codex CLI called a scalpel, and this resonates. You wouldn't use a scalpel for a major carving project.
To come back to my earlier comment, though, my main approach makes sense in this context. I let Opus do the abstract thinking, and then OpenAI's models handle the fine details.
On a side note, I've also spent a fair amount of time messing around around in Codex CLI as I have a Pro subscription. It rapidly becomes apparent that it does exactly what you tell it even if an obvious improvement is trivial. Opus is on the other end of the spectrum here. you have to be fairly explicit with Opus intructing it to not add spurious improvements.
Very interesting. I'm going to try this out. Thanks!