In terms of the macro focal length I think you need to consider potential use. Its not going to be great for insects of course but then again you could argue to do that well you need to be ALOT longer than 28mm on ASPC, probably more like 100mm.
I'v got an old GXR with the 33mm macro unit and that actually works very well on casual flower/fungi, hand holding a small body means getting in close isn't such an issue(not having to worry about tripod position) and has the advantage its less likely other vegetation will get in your way. Granted the Ricoh is only a 1:2 macro not 1.2:1 as the Canon is but with the ring light and IS I think shading and having to stop down a bit further would be less of an issue.
Generally I think the M system whilst not massive is moving in the kind of direction mirrroless should if its going to take up the mass market, Its less about creating "objects of desire" for gearheads and more about creating well performing lenses that people actually need for decent prices.