I'd like to see improvements to the current offerings rather than totally new products. Most have been mentioned. Relocate and better secure the strap lugs, longer EBL rangefinder, frameline options and better black paint on lenses.
I second these ideas - some things do need to be improved. Pain being one of them.
As far as new things - I'd like to see a fast 50mm lens, of course, same price as Nokton 35/1.2 would be fine. But it has to perform at least as well as 35/1.2 - sharpness, bokeh, character. If it's more like cv 40mm 1.4 - I wouldn't buy one.
All manual version of Zeiss Ikon/Bessa combo - i.e. Zeiss' VF and EBL in a Bessa-like body. Well made grip for it as well- would be nice.
Fast 25mm lens would be interesting.
Tri-Skopar - dont care about that one - compromise in quality and speed. Large and probably heavy. I don't mine large and heavy in a fast lens, but in a low one? Not for me. I prefer prime lenses for the best quality.
While far-fetched - I like the idea of MF camera with a killer faster lens, prefferably in a folder. Good and bright coupled VF/RF is a must. Meter is not, but would be nice.
Realistically, if Cosina could just copy Konica's - Hexar RF (2 versions - with AE and all manual), and all their lenses (Dual Hexanon is optional) at better prices, but as good optically - I'd be happy! Add 25mm 2.8 copy of Zeiss and thats really all needed for me.