Lot's of wish-lishes here.
But if Canon are to be serious they need to remedy where they (we) are hurting most, and it is not primarily in the long end.
Although in my opinion, every EF lens from 50mm and down should have been upgraded a long time ago, it is in no doubt that
Canon has for a long time been neglecting the wide angle department, and the current line up has been beaten by competition for a long time..
Now there are other lenses, but these are the most crucial IMO: (I have / or have had, all these lenses)
Canon EF 14 2.8 L II (2007) has bad IQ, lot's of CA/coma in the corners, beaten well by the Zoom lens 14-24 2.8 Nikon, as well as the Samyang 14mm.
Canon EF 16-35 2.8 L II (2007) has bad IQ,, lot's of CA/coma and soft in the corners. It has it's strengths in weight and portability but need an IQ upgrade.
Canon EF 24 1.4 L II (2008) has REALLY BAD IQ!! CA and so much coma in the corners that it basically useless in low lit sutations wide open. Beaten well by Samyang 24 1.4! Wake up Canon!!
Canon EF 35 1.4 L II (1998) has bad IQ, lot's of CA/coma/soft in the corners. An old lens well beaten by Samyang 35 1.4 and Sigma 35 1.4, needs an upgrade, but IMO 24 1.4 is more important to prioritize!
Canon EF 50 1.8 II, (1990), the oldest 50mm is the best 50mm Canon has. Corner sharpness is bad, but still beets all other 50mm from Canon, still this lens suffers from CA and is beaten well by the Nikon 50 1.8 and Sigma 50 1.4.
Canon EF 50 1.4 (1993) is suffering from severe CA wide open, well beaten by the Nikon 50 1.8 / Sigma 50 1.4.
Canon need to pull their finger out of wherever they are currently (the Cinema division) and respect and prioritize the DSLR customers which have put Canon where they are.
My top 3 wishes are:
1. I would like to hope that Canon are capable of producing an optical competitive UWA zoom lens to match/beat the Nikon 14-24 2.8 / Zeiss Distagon 15mm 2.8. Both these mentioned lenses are both better and cheaper than the Canon 14mm 2.8 II.
2. I would love to see an upgrade of the 16-35 2.8 with acceptable corner IQ.
3. I think Canon really need to replace the really bad 24 1.4 II !! The price/IQ here is out of proportions!