If it makes anyone feel any better, at least the blue dye rarity issue is historically accurate =P
Since there's no easily obtainable blue pigment that is so bright and *blue* (if you think about it indigo is probably the closest, but it is still quite purply unless very dilute). the only way to get sky or royal blue colours was to grind up gemstones like Lapis Lazuli - which makes the colour ultramarine. This was so rare and precious back in the days before synthetic colours that it was worth more than gold, was the reason renaissance artists needed rich patrons (Borgias, Medicis, etc), and was the reason it was only really used for the robes of figures like Jesus or, more particularly, Mary.
Sorry...tangentially relevant historical lecture. =P
Since, in Minecraft, you're using pre-coal tar dye methods for getting all the other colours...
Since there's no easily obtainable blue pigment that is so bright and *blue* (if you think about it indigo is probably the closest, but it is still quite purply unless very dilute). the only way to get sky or royal blue colours was to grind up gemstones like Lapis Lazuli - which makes the colour ultramarine. This was so rare and precious back in the days before synthetic colours that it was worth more than gold, was the reason renaissance artists needed rich patrons (Borgias, Medicis, etc), and was the reason it was only really used for the robes of figures like Jesus or, more particularly, Mary.
Sorry...tangentially relevant historical lecture. =P
Since, in Minecraft, you're using pre-coal tar dye methods for getting all the other colours...