You can set the color of your ships when you start a game by customizing your race. This isn't a "mod" since it's part of the core game functionality. Mods are things that alter how the game plays, such as rules changes, adding in tech, weapons, ship models you created outside of the game etc...

The UI is also designed to be moddable, and I think you'll be able to modify that as much as you like without it affecting the metaverse status.

try designing ur own "logo" and saving it in the file with the other logos stored somewhere amongst the game setup which i think is this C:\Program Files\Stardock\TotalGaming\GalCiv2\Gfx\Race . or if i skipped over the part where u said u didnt have the game maybe someone else give this ago. i know for a fact the UI was made to be extreamly changleble and i've seen pictures of ships that look like A-wings (starwars ship for anyone whos been under a rock) proving this to be true. and when i say A wings i dont mean they shaped it to kinda resemble it. i mean it was dead on screenshot from the starport menu with the tital "A wing"

I was concerned that if you added your own "paint" (insignia, logo, details, etc ...)

To do that you would need to edit the textures in the gfx folder. Graphics are pulled from the common gfx folder and not protected separately for meta games, so it should work just fine with no adverse effects.

As noted previously you can change the colors alone (keeping the same textures) in-game when you customize a race.