stepping out - the next textile piece - lots of grey

As well as going to the V&A last week, I have been working hard on developing the first large piece from my 37 steps series.  I'm aiming for it to be 37in wide by 74 high.  I've deliberately made it bigger, so I can cut it down to size afterwards.  Yesterday and today I've machine quilted solidly and there is still loads to do, but here are some in-progress photos, to prove I'm still working!
The background was a marbled fabric, which I painted grey. Some of the patches added are grey and the background stitching is grey.  When I was at college and we started dyeing fabric, one of the other students looked at the grey dye tin and wondered who on earth would want to use that.  I did!  It looked great to me as I was trying to make something based on the idea of the city.  I recently purchased a large bottle of grey fabric paint, elegantly called 'pewter' rather than grey (dye-na-flow made by Jacquard) and I've already used lots of it, just on this piece.  My aunt bought me some reels of Gutermann thread when her local post office closed and I've used virtually all of the 1,000m of grey.  Luckily I've found some more greys in my stash, several of which were passed on by my cousin, but I've going to have to get some more soon, especially if I carry on with more in the series. 

This is laying out the patches to be appliqued on.

First round of stitching on the coloured patches

First round of stitching on the 'plain' side