Hello, could you expand this part a bit? Would you recommend setting burn highlights to 0 for more accurate results, even if the scene isn't being overexposed at 0.25?
Nope, setting burn highlights to 0 does not mimic a more accurate result here, it is not properly color corrected for photorealism hence "AgX without the color correction". In any way, Blender's AgX/Filmic AgX is vastly superior.
The sole equivalence here is that both AgX/Filmic AgX and burn highlights=0 is fitting more dynamic ranges into the scene. However, AgX does clip some amount of brightness to retain photorealism, while setting burn highlights to 0 allow virtually unlimited dynamic ranges, which is NOT realistic to the eyes (as well as cameras).
IMO follow your artistic instincts. Depending on lighting conditions, 0.25 may work fine. If it doesn't that means lower the burn highlights to reduce unnatural clipping.
As an example, 0.25 burn highlights with multiple light sources
0.1 burn highlights