Was struggling a bit with Old World, so I dipped back into IS:G for a bit. Not gonna lie, I'm having more fun with the latter than the former.
It's nice to just enjoy a bit of "old school" space 4x, yet manages to not be slavish to the same, tired formula. I also forgot how much I like looking at a visually "clean" map, that's not too busy. The UI is relatively simple but functional; everything is generally pretty easy to find.
I never cease marveling at the brilliant remote exploration system; I still think it might IS:G's single best feature. I like how Outposts work, and how they can help expand/develop your empire without having to found a colony. Colony management isn't fancy, but it also means it's not complicated, and keeps down the micromanagement.
I've always really enjoyed the space culture perks, and I'm digging the new Evolution perks so far -- they're pretty powerful, and they genuinely feel like they're helping guide your empire/species in a certain direction. The new Minor Civilizations add some nice flavor, though I do wish they functioned a bit more like the minor races in Birth of the Federation. I'm also not wild about the fact that, currently, when I want to colonize a planet -- typically the only planets I *can* colonize at the time -- I'll automatically destroy any minor civs there, when I have no way of knowing yet whether any exist on said planet. It sounds like I'm not the only person who's complained about this, however, and the devs are looking at solutions to address it.
Critiques... The game's slow pacing in the beginning still bothers me, but it's admittedly not as bad as I remember it. Even with the tech tree set to Random, you're still probably going to get either Robotic Factories or Space Elevators available as an early technology (or both) -- either one of which provides a decent boost to your homeworld's industrial production, including shipbuilding speed. I could also really go for a larger map size of 400 stars or so (current largest is 280 stars, with close to half of them needing to be revealed via remote exploration), but it's not a deal-breaker.
I don't know that IS:G is ever going to be my "ultimate" space 4x game, but I'd certainly say it's a good one. And from what I've seen so far, the Evolving Empires expansion has only made it better. The Evolution perks in particular are fun to play with, and I think the Minor Civilizations will be a fun addition as well (or least, more so) once they're balanced properly.