Purely Cosmetic perks!
This gives you the ability to change your rank color name using /rankcolor (hexcode).
Keep in mind that Noble, Royal and Imperial are technically titles and not ranks.
Ranks are those you achieve through Voting and Playtime.
(this perk is included in the Imperial Title)
This gives you the ability to change your title color name using /titlecolor (hexcode) for purchased titles, and /hoftitlecolor (hexcode) for Hall of Fame titles.
Titles are things like Noble, Royal and Imperial along with the titles you get from being #1 in leaderboards.
This lets you choose the Rainbow glow!
This gives you the following items for a reduced price
Rank Color Changing
Title Color Changing (this perk is included in Imperial)
Extra: Rainbow Sheep Pet