As I said on the other thread, there is nothing wrong with a meat & two, served on a thrice-divided plate. It's how most of us plate at home most of the time. Such plating, however, doesn't make an aesthetic statement, which is why fine-dining chefs don't like it. They recognise that we eat first with our eyes, and try and appeal to that sense.
Keep that in mind. There is no right nor wrong about plating. Just ways of making that aesthetic statement. With that in mind:
One chronic problem with at-home plating is that we all have at least one set of "good" china. Unfortunately, most of the time, patterned china is about the plate, rather than about the food that goes on it. And that's true in this case. I find the floral pattern very distracting.
I don't fully subscribe to the white-only idea of many cooks and stylists. But I do feel that if you want the food to be the star the plate should be a solid, neutral color, or, at most, have minimal patterning. Imagine that plate, for instance, with just the two rings but without the floral.
Overall, you have not taken advantage of negative space. The effect is an overcrowded plate.
Whenever possible you want textural breaks. So the tomatoes, for instance, should have been shingled rather than laid flat in a row. Personally, I don't care for little cubes of cheese like that, and would have gone with thin slices instead. And I'd have gotten some fresh herbs on the 'maters.
More than likely I would have served the asparagus in a seperate, appropriately sized, dish. But, if not (which means an oversized plate rather than the standard one you used) I would have either triangled them, as Nicko suggests, or woven them.
As to the chicken, it really depends on your plating goal. A basic rule of fine dining is that nothing inedible goes on the plate, ever! If you want to plate that way, the bone has to go. For at-home, with no special guests, you probably don't care. But I find it worth the effort, and would not have served with the bone in. Point of fact, I would have presliced the chicken, and fanned it out on a smaller puddle of sauce, and lightly drizzled a little more sauce over the slices.
Although I plate restaurant style at home (heck, there's just the two of us, so why not?), I'm not as obsessive about edge splatters as I would be in a restaurant. A tiny drip or two wouldn't bother me. But your edge is sloppy. You've got sauce oozing onto the rim from the asparagus, and another glob of it dripping off the chicken. The former results from the aspargus being too large for where it's plated (it should be contained by the inner circle). The latter likely just that you didn't notice it.
All that said, let me also note that if I were a normal at-home cook, there would actually be just a few changes I'd make to that plate.
1. Change the china (and maybe not even do that).
2. Bone the chicken.
3. Make the asparagus smaller, so it fits better on the plate.
4. Shingle the tomatoes.
In other words, even the plate-divided-in three can be made more visually appealing, without a lot of stylistic techniques.