Sins of a Solar Empire is an awesome, awesome game, especially with their new Entrenchment expansion. Last night I beat my first opponent on Hard mode, and I think it makes for an interesting story:

I was playing as the Vasari, a race of high-tech aliens with expensive but powerful ships, marked in green above. My opponents were the Verlin Descendants, a human faction with cheaper ships, marked in red.
I had pressed as far as Cesaro (one of the terran worlds in the east on the map above) with little resistance, but the humans had gotten going a little faster than me and had taken over Echemmon before I got there. I set up ship factories on Cesaro, built carriers full of bomber squadrons, destroyed their starbase at Echemmon, and took over the planet. I had built my own starbase there, but neglected to upgrade its armor and weapons, thinking that the remainder of my fleet and the starbase could handle anything the humans could throw at me.
This, it turns out, was an error. Before long, the humans sent in a massive fleet, with a lot of Ogrov Torpedo Cruisers, ships designed to take out structures like starbases, and with a lot of Flak frigates, designed to shoot down my bomber squadrons. In seconds my starbase was reduced to dust, and I was forced to pull back. Their fleet chased me out of Cesaro, destroying my factories and my pitiful local defenses and decimating my fleet. I pulled back to Dione.
I had expected the humans to pursue me again, but they did not. Perhaps they wanted to tend to their new conquests. Maybe they thought I held a fleet in reserve. Maybe they were afraid my fleet would jump back to Cesaro and take out their new buildings while they attacked. Or maybe they feared Dione’s more powerful starbase, which had much thicker armor and more powerful weapons.

In any case, I was sure I was going to lose the conflict. They had a larger fleet and access to more resources. I kept waiting for them to press their advantage, but apart from brief, smaller raids on Dione, which my fleet and the starbase easily swatted away, they seemed to be leaving me alone.
I set about rebuilding my fleet, doing research into ever more powerful shields, armor, and hull designs, and pondered how I might salvage the situation. Then it came to me: I would build a Kostura Cannon.
Now, I need to explain something about how the game mechanics here: You see those lines on the map? Those indicate the paths that ships have to travel. So even though my home planet of Weierstrass and their home planet of Minox are right next to each other physically, I’d have to jump to five different planets to get there.
But there is an exception: The Vasari have a technology that lets them build Phase Gates. A friendly ship can go directly from any planet with a phase gate to any other planet with a phase gate, bypassing the long trip from planet to planet to planet.
The Kostura Cannon is a large, expensive orbital weapon that can shoot at any planet, damaging every ship and structure in orbit. More importantly, it also temporarily makes that planet a phase stabilizer node, meaning that any ship at a planet with a phase gate can jump directly to it.
It was a big gamble: I had to build several new research labs, spend a lot of money on building a prototype, and then wait while I accumulated enough resources to build the cannon itself. All the while, I expected the humans to attack–instead, I discovered later, they were building broadcast centers, attempting to take over my planets using a propaganda campaign. It nearly worked too, but I built my own media hubs just barely in time to save Dione from rebellion.
Eventually, the cannon was finished and my fleet was rebuilt. I fired the cannon at their homeworld and sent in dozens of ships. Their fleet was badly out of position, and I was able to bombard their home planet–and their Capital Ship Factory–into oblivion before they could respond.

Meanwhile, I was building more ships and researching more technologies. I readied the cannon again and fired at Akhmatova, and sent even more ships into their back lines. This second fleet included a Migrator, which I used to build a starbase in orbit above their planet. The starbase was quickly outfitted with its own phase stabilizer nodes, allowing my ships a permanent direct path past their defenses at Terradas.
Their fleet eventually arrived, but it was too late. They had spend too much of their resource advantage trying to expand by culture; their fleet was not much larger than the one that had chased me out of Echemmon. I was able to crush their fleet and take over everything from Minox to Artemis before they surrendered.