I have several fans that support directional brightness dimming. This is not currently handled by your drivers. Because it is not handled, the light child device is the non-dimming driver.
I did a bit of debugging already.

The output of state.fanDetails[fan] is: [TurnOff, SetSpeed, SetDirection, ToggleLight, StartIncreasingBrightness, StartDecreasingBrightness, OEMTimer, OEMRandom, Stop, TogglePower, TurnOn, IncreaseSpeed, DecreaseSpeed, ToggleDirection, TurnLightOn, TurnLightOff]

The key terms are "StartIncreasingBrightness" and "StartDecreasingBrightness"

Neither of your current Light drivers handle this as far as I can tell. "BOND_Fan_Time_Light" is closest but needs the concept of direction.

I suspect, this would also fix at least part of #4