My two cents worth would be to extend the tiles to cover everything below the canopy of the extractor (could go higher but that would be the minimum) and use that as your level on the other wall. So you ignore the curved glass (I assume that that's kind of the point of being transparent) and go with the straight edges of the tiles. You certainly wouldn't want a funny little segment of painted wall below the curved glass – it will look awkward and be very difficult to keep clean. My remaining concern is – have you already installed the rangehood or can it be easily taken back down to allow the tiler to do a really good, neat job and then the rangehood can be installed nice and tight against the tiles?

I work in tiles all day. Glass and mirrored splash backs are on the way out. Texture is what everyone is chasing now. Lots of interesting textures and tile shapes coming in particularly hand made looks in gloss and mat. Maybe 150 x 75 mat laid in a herringbone style (45 degree) or black gloss or matt laid brick or h/bone with contrasting grout. For a modern look 600 x 300 size tiles with grooves in mat finish. Bright colours with black and cream such as red are great if you like them but if you plan to sell the majority of people don't seem to like bright colours in tiles and your colours are classic at the moment.

Forget subways, really overdone & can look so cheap. The more grout you have the more cleaning you'll have to do. It collects grime ( known in the trade as 'grotty grout' ) & is hard to maintain. Go for glass, the possibilities are endless, from sophisticated plain to funky patterned. Easy care & long lasting. Personalise your space, it looks really fab, love all your drawers, so practical ! Would love to see the end result. Please post pics.

You will have to remove to repair, and then it might break anyway. Re-asses once the mirror is off the wall, as to whether the glass can be re-silvered to form a complete mirror again, or whether the glass is too damaged.