ofafeather wrote in post #18370822
I think portability is the first key. I have some great lenses for the 5DII but would love to have something more discreet to carry around on trips to the city or light travel. I haven't really thought about the focal length or ASP-C vs 4/3 format. A flexible set-up for street photography, light architectural and landscapes, candids. Of course low-light performance would be great but I know it's somewhat limited compared to a FF with a fast prime. So maybe a fast prime and versatile zoom?
Well then Fuji, Sony, or M43 will get you quite a bit smaller with good flexibility. I used to use an M43 camera (Panasonic GX1) as a second system but wasn't not impressed with it so sold it off. I picked up Fuji a couple years later, again as a second system, and like it so much I switched completely. With that said I have heard then the quality of M43 has increased quite a bit over the last few years.
So now the question is, are you ok with the smaller M43 sensor or do you want to stick with the slightly bigger APS-C sensor? Now for lenses. M43 has a large selection, not all are great but with so many to choose from its easy to find exactly what you want. Fuji has a smaller selection of lenses but you have to look hard to find a bad lens in the X-mount. I personally think Sony's lens selection is the weakest of the bunch with a small selection and noting really great (in e-mount for aps-c).
I'm a fuji guy so I'd suggest looking at the x-t20 and then find lenses that fit what you need. The 18-55mm f2.8-4 is probably the best "ket lens" made by anyone. Fast primes? Fuji has lots of fast primes. 16mm f1.4, 18mm f2, 23mm f1.4, 23mm f2, 35mm f1.4, 35mm f2, 50mm f2, 56mm f1.2, 90mm f2, and 14mm f2.8 if f2.8 is fast to you.
For what you said you're looking to shoot the x-t20 with 18-55 and 14 might work.