Some time between 2000-2004, i think, i bought a pc game where the plot is aliens have attacked earth and left the planet in ruins, we took one of their ships and reverse engineered it and are setting out after them for revenge. The gameplay was rts resource management that felt similar to command on conquer. The unique aspect was the world maps were full 360 spheres that you couldn’t see all at once and had to rotate. You could ship resources between conquered planets but it took time and the enemy could try and retake a world after you left.
Was it Universe At War. I think its a little more recent than that but sounds similar.
It does sound very similar but you are correct, too new of a game to be the one i’m trying to remember