Advice on colors

[Drachenfire]

Hello,

This might be a shot in the dark, but I am posting to ask for advice on how to arrange colors in a kingdom.

I wish to use a nice purple in a realm, something that evokes an affinity with Rome, but is not the empire’s specific purple. Additionally, how would you recommend the placement of darker hues then lighter ones in the realm. Is there a science to this?

Thanks