I agree with fireflybob.
The BEST days by far are the ones in crap weather, with slots, delays, discretion, diversions, passenger faff, bad ATC, tech aeroplanes, etc etc. but with a really fantastic crew so the whole thing still feels like it's running on rails.
The WORST days are the days when it DOES actually run on rails....but you have to fly with a complete and total kn0bber in the seat next to you....just like today....