I'm definitely going to machine embroider over the canvas prior to quilting it. This is because of the durability problem(s) of tapestry stitches as previously mentioned. It would also use up a rather large surplus stock of cotton threads as well as providing another textural layer on top of the stitched wool one. Additionally, the quilting shapes will become more prominent when finally stitched since there will be less stitching needed to hold the fabric together (here's hoping the machine embroidery will do its job!
I first pinned together the canvas, its fine net top layer and a fine fabric layer underneath (to prevent stitches snagging when machined I used a recycled net curtain remnant). Random selected stitched ' shapes' were outlined by machine in straight stitch to hold the 3 layers together instead of pins. Overall, this was started in the centre of the panel and was worked towards the outside. It was difficult to control the fabric tensions 100% but I'm hoping the top net layer (which caused the canvas to pucker in places) can be stretched slightly when machine embroidered.
A small initial area close to the centre has been started using a cotton thread in a colour similar to the wool. Free zig-zag stitch has been used, following along the pattern shapes of the wool stitching. So far, the net is stretching quite well and flattening the area out (photo of this to come).
It looks as if the machining will take longer than anticipated ... NEXT ENTRY should show how far I've got!