First, I have all the sensors as I'd rather resolve an issue as it occurs rather than in the aftermath.
The swage sensor is there to recognize a ringer. It might be an undecapped primer or a primer that has disintegrated and left a ring. The issue is it can cause a jam at the priming station (many minutes taking it apart and re-assembling if you have a collator) or you end up with a round with no primer spilling powder all over the place.
The powder sense is there to catch if there is an issue with the dispenser so it dispenses no powder also if you jog up or down after torque sense sometimes it skips dispensing powder when starting. This catches it if/when it occurs rather than single cycling a few times and going to the back of the press to check, again time saver and of course a safety check.
Also, having all the sensors means I can pay less attention and utilize my time dry firing in 5 minute increments, then stop dump bullets/primers and dry fire for 5 more minutes while the press keeps going