Leica could end this discussion if they would offer a fully identical Q2 with either a 28, 35 or 50 mm fixed lens. Then every client could select the lens that suits him best. And I would chose a 35mm version.
I understand that's expensive and perhaps too complicated to offer such an option. So it seems logic they took a 28 because you can crop to 35 and higher, where with a 50mm you can not "uncrop" to a 28.
After a M9-P with multiple lenses of which 80% of the time I used the Summilux 35mm, I'm very happy with my new Q2, it's lighter, more compact and offers a lot of nice to haves.