AutoCAD 2010 :: Blocks And Lines Color For Projects?

I work with ground floor plans and what kind of color I should use for the blocks and lines.

For example:

Today, i try to keep this kind of lines, but I saw other drawings with different colors and I wondered if I doing this correctly?

I list below my layer colors:

- new equipment = green or blue or pink;

- existent equipments = gray lines;

- existent walls = gray or white lines

- new building walls = red lines;

- demolished walls = yellow lines.