Really very interesting, thank you for that matrix. It obviously took you a great amount of time and effort and I can tell you put a lot of thought into it, so, it's lovely you are sharing!
I personally use a software that determines my price. I entered in the ingredient prices, KW/h or my energy costs (my kitchen is all electric) plus prices for packaging, boxes, parchment paper, cake tin liners, etc, (a one time job which took AGES), and that formed the database. I then can just enter in a type and size of cake, what filling, frosting/icing, which embellishments are being used and it tells me the price based on my actual cost and mark-up. It also takes into account my fluctuating fuel costs based upon mileage, well, just everything. It was an expensive one-time purchase, but for me, it was worth it.
What I like about your matrix, (and about Alice's which is on this site,) is that you tell people to look at ALL costs involved. Often people forget about the cost of sticks for cookie bouquets, having to buy in a special colour for cake embellishments to match a bride's palette, how much parchment costs to line a tin, or wrapping their cake layers in plastic wrap for freezing and it all adds up! You want your clients to eat your cake, not YOU eat the profit.