Have you done machine applique before? Because, if you haven't, you may run into some problems with this idea. This is because it is *very* easy when appliqueing large shapes onto a background fabric to end up with distorted background fabric. When sewing in a circle, a lot of the sewing is on the bias of the background fabric and the bias is notorious for stretching. When I applique on blocks I make sure that the background fabric is *very heavily starched* so that it is much less likely to stretch and distort as I sew. I also like to starch the applique so that it also is stabilized.
I would strongly recommend that you applique a practice plate to a background square to make sure you understand how the backing fabric will be affected. If you do not starch heavily, you will almost certainly finish only to find unacceptable distortion in the background fabric when you are done. This is the reason why I would advocate against the idea of trying to applique all of the plates to a single large piece of fabric. Even if you starch the large piece heavily, it will lose some of its stability as you manipulate the fabric underneath the arm of your machine. If you do try this, I would recommend doing several additional layers of spray starch on the next area of applique before sewing. In other words, heavily starch the background fabric, then before each plate add some layers of spray starch to the background area for that individual plate.
I also think you would find it tiring manipulating all that fabric underneath the arm of your machine as you sew around each plate, even if you can stabilize the background sufficiently. So much excess fabric will also make it more difficult to applique accurately.
These are the major reasons why the standard method is to applique onto individual blocks, then sew the blocks together. While it's possible to do it on one big piece of background fabric, most people who do machine applique would shy away from that. If you are not experienced with machine applique, you will probably run into a lot of problems you didn't expect.