Nice, Gauntlet.

As a big-time geek, I've read most of the Halo books, as well as memorised all the games. There is definatly enough material on the covenant side to create a race, and on the UNSC side as well- but you would probably have to make do with one or two ships per size- Check the following two pages:
http://halo.wikia.com/wiki/D77H-TCI_Pelican
http://halo.wikia.com/wiki/Covenant_Destroyer

You could reasonably get perhaps 5 races out of this- The Covenant (The Elites), The Covenant (The Prophets), The UNSC, The Pirates, and if you were feeling adventurous, the Sentinels (They were the pesky robots from Halo that alternated between killing the Flood and the player. The book Halo: Ghosts of Onyx showed that they are capeable of combining into larger and more powerfull robots, capeable of taking down a Covenant cruiser)

Yeah, I'm such a geek.

I don't get it... what do you want to do with this mod?

As I see it, perhaps you can enlighten me, the only thing you would add is ships and races. People, you can do that without modding! I suppose you could add one or two invasion styles, but it is still going to be GC2, with an extra ship designed, a cool custom race, and, if we are lucky, perhaps an invasion style!

Guys i am looking for a halo mod where I have covenant ships i have a custom race its sangheili's (elites) cuzz im a big sangheili fan and i would be thankful if some one made thease ships for me. 

1.Phantom

2.Banshee fighter

3.covenant battlecruiser

4.Covenant corvette

5.covenant battleship

6.covenant cruiser

7.covenant destroyer

8.covenant seraph

If anything all I really want is the corvette but please help if anyone can. And Atlan I ve played all the games read all the books and watched all the movies (but my favorite book was contact Harvest)