Not a fast 50, but there's a fast (Leica f1.4) 25, equivalent to a full-frame 50 in terms of angle of view. The 14-35 f2 is similarly equivalent to a 28-70 f2, so pretty tempting, and I would forgive the 12-60 f2.8-4 it's non-constant aperture given the range. Not a massive choice, agreed, but a pretty useful couple of lenses. And yes, there is a 2x.

Most of my macro stuff is ferkin' flowers, so actually frame filling is the key, and the smaller format means you don't actually need the same reproduction ratios, and the Oly macros would be good enough for me. So yes, I would miss the lightweight primes, perhaps especially because Olympus always used to do them so well for OM, but it wouldn't really cramp my photographic style.