I've had a long game of the SOASE mod, "Requiem" going on for several weeks. I play a few hours here and there when I have time.
The game started with two players of each race, allied together with locked teams. In Requiem, the races are: TEC, Advent, Vasari, and the main Star Wars races of the Galactic Empire and the Rebel Alliance. I put all the AIs on Unfair to make it a truly epic game.
The game has lasted over 26 hours now (not real time, because I ran the game quite a lot at 8x speed to accumulate resources in the latter part of the game). Within the first 6 hours, all factions had been defeated, except for the two Vasari, myself (as Galactic Empire), and my ally, also Empire. The TEC were the first to die off; I think they got caught in the crossfire between the Vasari and the Rebels. The Advent were defeated just a short while after that. The Rebels managed to fend off the Vasari for a while, but eventually the Vasari overwhelmed them, too. During all of this, my ally and I were basically just turtling up our defenses and slowly expanding. I had a rather meager empire with only five sectors as my core worlds (that I colonized uncontested). My ally lucked out and scored 9 planets before bumping against the borders of a very powerful Vasari adversary.
For those first 6 hours, the biggest threat to me (or so I thought) was one of the Rebel factions. They made somewhat predictable attacks on my border worlds with large fleets of combat frigates and capital ships. My starbases fended them off though; it wasn't too bad.
After the Rebels were defeated, I soon realized the Vasari are way more powerful in this mod than the other races. It's going to take a lot of slow buildup to overcome them as the Empire. The main problem is that the heavy cruisers of the Empire are extremely expensive, both in terms of resources and supply. So to make an assault on an enemy world, I inevitably lose a few heavy cruisers (Loronar Strike Cruisers to be exact) during the firefight, which means as much as a half hour of rebuilding after I clear the sector.
My current situation is looking better though: I have reached the supply limit for both capships and cruisers, and most of my capships are level 9 or 10. Most of them are the most durable class of capship, the Imperial II Star Destroyer. For flavor (and a nice mix of special abilities), I also chose to have two Imperator-class Star Destroyers and one Victory IIc Star Destroyer. I have to watch the latter very carefully because its shielding and armor are a fraction of the Imperial II's. In terms of system ownership, the combined colonies of my ally and I exceed that of the Vasari by a modest amount, so we're on the downhill slope. Unfortunately I don't expect any surprising coup d'etat from the AI, so the game will probably end in a predictable, slow win for my ally and I. I might just call it "good enough" as it is, and move on to another mod. Such a great game, but it's starting to grate on my patience.