The primary objective of this strategy is quite simple: economy. Instead of building extravagant fleets early in the game comprised of small frigates, build only two capitals and a titan. Fleet supply serves to cripple an economy and defensive structures require none. I have employed this strategy against vicious and cruel AI, and providing the map doesn’t have the enemy homeworld a couple phasejumps from mine, I almost always prevail.
Step 1: Build a colony capital ship and that ship only and set about colonizing worlds at quickly as possible sealing off some planets to be colonized at a later time so as to stop your foes from getting them. On newly acquired planets, upgrade population to the maximum and build trade ports since it will pay off long term.
Step 2: Build a second capital ship, preferably one with regenerative abilities, and have it aid the former ship. Once you have established a border with only two or three possible avenues of attack, add defense structures and eventually a starbase at these border planets.
Step 3: After spending a sufficient amount on defense, invest in building a titan and since your economy will be rather strong it should not take more than 5 minutes to acquire the resources. As soon as it has finished production, send it straight to the nearest enemy planet. When its health runs low retreat it to your fortified planet to be repaired. And after utilizing this guerrilla warfare with your titan and capital ships they will have leveled up many times and perhaps you will have even conquered a few planets.
Step 4: After about two hours into the game you will have amassed 200,000 or so credits and at this point you may expand your fleet and finish the job. If you have survived the first hour of the game without taking significant losses, victory is yours as your opponent’s economy will be devastated and his fleet will be broken on your defenses like water upon rocks.
Note: This strategy is best implemented as the Vasari rebel faction due to their mobile starbases and survivable titan.