Not a 'personal' remark, but maybe you've always used middle-of-the-road ordinary 50mm lenses that always perform OK with no particular qualities to them? I've had 4 different 50s (if I include the Zeiss 55) on my A7, and all of them give a different appearance to pictures:
Minolta A mount AF 50 f1.7 is a boring middle of the road 50 that's just sharp enough, tolerable bokeh, functional and similar to any other nifty fifty.
Sony/Minolta A mount AF 50 f1.4 has coma by the bucketful wide open, and gives a beautifully smooth, almost glowing rendering with soft corners and smooth bokeh when wide open.
Samyang 50 f1.4 FE had wafer-thin DoF at f1.4, fantastic subject separation and a very neutral rendering - I'd love another.
Zeiss 55 f1.8 FE is sharp enough to cut, even at f1.8, and at f2.8 is incredibly detailed right out to the corners, very neutral, very contrasty.
Example of the Sony 50 f1.4 - the glow is all the lens.
Yamaha SR500 2 by
Toni Ertl, on Flickr
Exampl of the Samyang 50 f1.4 FE
Dance on the wind by
Toni Ertl, on Flickr
Example of the 55 f1.8
Moonlight shadow 2 by
Toni Ertl, on Flickr