I love this game, and i think it is one of best looking RTS's from its time (2002?) + its stupidly hard even on easy.
Great game going to have to dig it out now and replay....
Never understand why people say its hard, i think its to easy on the hardest settings.
some tips
1, Remember your mothership can move so move it up as close as possible to the enemies strong holds it makes reinforcements quicker.
2, Capture those capitols, nothing like having frigates, destroyers or battleships several levels before you can build them.
3, Take out the enemy's production capabilities as quickly as possible. if they cant build they cant attack.
4, Keep a fleet of bombers in reserve, never know when you need to take out something big quickly. They are also useful as hit and run on capitals, a full fleet can take out the main guns on a battleship in one pass.
5, Set repair corvettes and any thing else that can repair your ships to guard your capitols (might be repair cant remember) they will auto repair any ships that get damaged in combat. This will double or even tripple the damage a ship takes before its destroyed.
6, If things arnt going well retreat and regroup.