My favorite reds are darker reds; but red's never been much of a favorite at all. My big favorites are on the blue side of blue green, and blue-greys. Blue steel is a favorite metal for that reason, even if there's no practical application for it.

Though, it's interesting, in the history of swordsmithing, meteoric iron has been tried, and that also usually produces blue steel, due to the high nickel content common in meteoric iron. That that it has any desirable effect on the sword's sharpness or durability, but it looks cool.