nozzer, sorry for the bad experience, it doesn't look good.
I can think of 2 options to disguise the corner - a shelving unit as you suggested or you can probably take off the thin strip of tiles and replace it with a decorative strip - mosaic tiles or chrome coloured tile strip and make a feature of it.
I personally if the finances allow would take the whole wall off and retile because the window is the first thing you see entering the bathroom and it is really annoying to have the tiles around not centred.
I can think of 2 options to disguise the corner - a shelving unit as you suggested or you can probably take off the thin strip of tiles and replace it with a decorative strip - mosaic tiles or chrome coloured tile strip and make a feature of it.
I personally if the finances allow would take the whole wall off and retile because the window is the first thing you see entering the bathroom and it is really annoying to have the tiles around not centred.