I don't have very concrete suggestions, but a way of thinking about how I approach my work:
A first aspect should be the material that you would like to have in that spot.
Of course: the price plays an important role in such a decision, but in my experience, one should only check how expensive a plan would be very late in the process so that creativity is not stifled by it.
Often you notice or think of things you otherwise wouldn't have come up with.
If it should be concrete, I would try to emphasize its properties (the pun is a coincidence).
One possibility for this, in my opinion, would be to cast a massive base and then grind its surface.
Depending on the size and type of gravel used, you can then see the stones – because they're ground – as round small or larger surfaces, as you know from "terrazzo."
I designed a terrace like this and am very happy with it, among other things because it is so solid. Tiles can't come loose or anything like that – the surface doesn't need to be "designed" separately. The material is visible (and looks good to my taste). Here is a picture of the unfinished installation:
[ATTACH alt="TerrasseRegen.jpg" type="full"]45953[/ATTACH]
The surface was not polished so that you don't slip when it rains.
If you have a bit of craft skill, you can also consider grinding the piece yourself. In my estimation, an angle grinder with a grinding disc is enough. The terrace at my place was ground by a professional, with machines that cost many thousands... but that wouldn't be necessary for a size of 2 square meters.
Of course, a surface won't be as precise with an angle grinder, but "handmade" has its own charm – which varies depending on the hand that made it.
You can largely determine the color with this method. Concrete can be well colored with pigments, and if I remember correctly, there is even white concrete, which is certainly more expensive but allows for even more color variation. (Otherwise, like a painter, you have to include the gray of normal concrete.)
More noble – but also much more elaborate – I would find a large stone block... for which in my eyes the same applies as for concrete: the language of the material should be emphasized.