Glad to have these insights. Still on the fence between adopting the M3 or abandoning the M system to get a xxxD second body. If Canon would release a down-scaled 17-55mm f/2.8 for M, or a couple more small, fast primes, that might make the biggest difference. Or a compact macro. Much as I like the 22mm, the 18-55 is just too slow; the 11-22 is too pricey; and the 55-200 is physically too long and way too slow (and just about useless unless AF really is worlds faster on M3).
With a tiny body that lacks a truly substantial grip, the handling of any zoom lens (other than maybe a theoretical power zoom) is going to be dicey because the torque applied to the zoom ring can be enough to destabilize your grip on the camera body--particularly when holding the camera out from your body to compose on an LCD. A stiff ring like on the Tamron 24-70mm VC makes it useless in combination with the M. Primes just handle better.
I think I may be convincing myself to bag it and just go with a Rebel T6s (760D).
Not trying to hijack this thread, but have you considered the Canon SL1/100D? That's what I use as a smaller, lighter alternative to my 5D3. For me, the SL1 had more advantages and was a better fit than the EOS M. All my L lenses fit on it, no adapter needed (although I have the 18-55 and 55-250 lenses as well). Handling is very good, much like a regular SLR. Image quality is superb. And the whole kit fits into a small Crumpler bag that is easy and light to tote around.
To me, if you already own a larger Canon camera and accessories, the SL1 is a perfect addition if you are looking for something smaller and lighter.
It also makes a great easy-to-use camera for a wife or girlfriend.