Another thought: If a 0.5 Hz corner freq in the feedback loop (not the through-path) still is not acceptable, consider using the other half of the LM358 as a DC servo. This is how it's done in some audio power amplifiers with a DC signal path.

ak

 

Not sure if I need that level of perfection, but here is a good reference I found on servo's. https://sound-au.com/articles/dc-servo.htm