I try to keep the signal within the realm of appropriate at every point where it can be reasonably controlled. I try to keep a good S/N ratio while recording, the clip would then be automatically fine, I keep the peaks for each track and its sends below 0 dB and same with the master output except that the peaks on the final master output might be even lower if the piece is best set at a lower volume.
Some audio engines run at floating point so that the initial clip and the final fader are all that matters, but I retain my habit developed in analog days when a signal rated at 0 dB would meter at 0 dB at each section of the audio chain until there was a reason to make it otherwise.
Just the master although I tend to use a color Curve to just roll off the highlights to preserve as much detail as possible. Basically I'm Legalising the footage. Once you start fiddling with each clip you're grading. That takes skill, a good monitor and an hourly rate to match when it isn't your footage.
The new track will be rendered with the FX on the buss master applied. The alternative would be just as suspect depending on user intent. There is an FX bypass button in the master track header to give the user the choice.
Hardly rates as "dangerous", keeping the scopes open and checking what I'm doing has yet to let me down.