If you refer to the second image, i did that on purpose. Focusing the sink and the water (and i did it) did not emphasize the whole image, it looked pointless and also phony, even if it was a standard/correct depth of field. When i tried to focus the soap and the beginning of the wall on the right, i was pretty happy with the result.
I'm pretty sure that the chair is in a correct scale. I agree about the sink material, it should be less reflective as the bidet and the toilet; i probably multiplied it in ps without paying enough attention.
Thanks guys for your C&C, keep it up!