I don't like all pinwheels, and I don't like all squares either. I love the first one with a pinwheel here and there. I see five of them in that layout. It makes you look around more to see what you can find. With the all-pinwheels layout, it may be more interesting if there where a square or five to break up the monotony.
Love your colors, and your English is almost perfect. Congratulations on being bi-lingual. Wish more of us were.