Lens upgrade advice
1) @ f8-11, i don't think you'll see much IQ difference comparing the 14 and 17-40. So the deciding factor is not the IQ but whether you really need that extra 3mm vs versatility.
I definitely will appreciate 2.8 aperture and 3 mm wider lens, I probably trying to convince myself that extra cost will worth it.
2) It's a known fact the 70-200 2.8 mk II trumps mk I, I m surprised that you are surprised
I've heard a lot of reports, but never had a chance to try it myself.
I am pretty sure I will go for upgrade.