So, taking this long to get to two hours probably doesn't have anything to do with the game itself. I kept falling asleep while playing it, but that's most likely because my last couple of days have been pretty busy.
As far as the game itself, it is a lot like Sins of a Solar Empire: Trinity, so much so that I've realized I am completely unclear on the basic structure of the series. Is this a sequel, a standalone expansion pack, or something else (looked it up - Trinity is a bundle of the original game and the first two expansions, Rebellion is a standalone expansion)? There are some new factions, which is nice, though I'm playing one of the originals, and it feels very familiar. There's also some new planet types and new ship classes, but I haven't found any of those yet either.
This wouldn't be the first time that I've played two more or less identical games for the blog. It's always a tricky line to walk, because I want to engage with each game on its unique merits, but I tend to start thinking of the series as a single unit. Sins of a Solar Empire isn't doing itself any favors in this regard, but I'm hoping that there will be more divergence in the late game.
In the meantime, the basic Sins of a Solar Empire gameplay remains pretty solid, if not in a genre I particularly enjoy. I'll probably just keep plugging on . . . provided I can keep my eyes open.