I agree with ICK about the sink (I hadn't noticed that). Maybe you could move it to the other end of the bench so it looks out at the dining area and through to the entertaining area/backyard?
I also agree about the window in the ensuite being on the front. How about adding another window between the toilet and vanity? That means you could have window coverings on the front one which remain closed for privacy (such as blinds), but you can open the side window coverings to let plenty of light in.
I don't like the location of the linen cupboard either. If you are going to widen the garage slightly (if the block is wide enough) I would sink it into the garage wall. Or move it to the laundry/garage wall with the doors opening on the laundry side.