Lets keep it simple, ok? Short and sweet. The KEY reasons of owning a FX camera is reducable to four things:
1. Ultrawide lenses, both prime and zoom for landscape work
2. Lens compression of framed subject face/body (A 56mm on DX is still a 56mm, despite being a 85mm FOV)
3. To get "great" bokeh requires less a shallow DOF at a given focal (85mm at 1.8 requires a 56mm at 1.4 or faster)
4. Pixel pitch (all exposure is gain and time) on MOST (some are DX pitch) FX cameras is such that shadow recovery and DR is much better
One LIVES within these limitations. DX itself has advantages over FX (pixel pitch for cropping for wildlife photography).
All in life is a trade-off, deal with it (or own both, as most pros do).
