Well, you could argue that a MFT camera plus the 10-25mm f/1.7 is still more lightweight and compact than a S1 plus the 20-60mmm f/3.5-5.6. And it's a bit faster too.
Chief Editor - opticallimits.com
Doing all things Canon, MFT, Sony and Fuji
Indeed, but the difference in size might be considerable (in favor of the FF setup) the day Panasonic releases a GX version of their FF body ;-)
Also I'd consider the 20-60 a landscape lens, therefore the f5.6 at the long end doesn't bother me.
I'd typically take this 20-60 lens along a fast prime (in the 35-50 range with a f1.8 aperture).
This would be my perfect setup.
I'd consider the 20-35mm end indeed "landscape" lens, and 50-60mm normal focal length, where at times the extra 1 1/3rd of a stop can come in handy, and save me from needing to take along a 50/55mm faster prime every time.
I either take my 35-70mm f3.5-4.5 and 20mm f3.5 with me, or a 55mm f1.2 and 20mm f3.5. So I can kinda relate.