Just a note on Pro Tools. The TDM version of PT uses a 48 bit path when summing, It can handle quite a few tracks at full scale before clipping, so lowering the fader in this case is essentailly the same as lowering all of the tracks (and doesn't require you to remix). Check out the digidesign white paper for a full explanation.
The definitive answer is to know how your DAW works internally and work within its limitations.
Recording hotter creates a better signal to noise ratio, but in digital it really isn't too much of an issue. Recording hot to tape was to take advantage of its natural compression abilities and "sound" as well as signal to noise. In either case you have to balance the pros with the potential issue of generating distortion. You can be either too safe or too aggressive.