I have only two zooms, the amazing ultra-portable Panasonic combo of 12-32/3.5-5.6 and 35-100/4.0-5.6. I always takes these two for travel and for landscape shoots.
Current prime collection:
Panasonic 15/1.7 - Bought the DJI version cheaply and optically it might be my best lens. Also like the aperture ring, makes me feel like I'm shooting Fujifilm or Leica
But as much as I try, still not really comfortable with it. I carry it mainly as low light alternative for some trips where I take the Panasonic zoom combo. It was very useful for night photography of city in Beijing and Tokyo. Nowadays trying it more on GF9 for night street photography.
Panasonic 20/1.7 - Love this tiny guy, perfect fit for both my GF9 and EM10ii and used it sooo much. For some trips, it was on my camera 90% of time. If it had better focus in dark on Olympus body, it could be my only lens.
Panasonic 25/1.7 - 50mm lens is really fitting me, used as my daily carry on old GF1 and taking it for most of my streetshoot walks. Just seems my copy isn't the sharpest, even when step down.
Olympus 45/1.8 - Not used as much, but anytime I take it for portrait or street, resulting photos are just lovely. I think I should start carrying it around more and be more willing to switch to it.
Currently I'm not sure if I want to add any lens. Might just buy cheaply another Pana 25/1.7 to see, if my copy is truly as bad as I think.