It's too early for me to say for certain yet, but I think GC4 may have finally addressed one of the main weaknesses in the series' previous iterations: the economy.
Specifically, it was often difficult to know whether -- or how much -- constructing a given building on a given tile on a planet would improve your manufacturing/research/income/etc. output. Even now, it's admittedly still not always clear, but both building stats and the UI are better presented & laid out so as to make things easier to understand overall.
On a different note: One change I really like that is that all Starbases, regardless of type (Mining, Military, Communications, Economic) now include some degree of "harvest" ability, which means they automatically siphon up a portion of any & all strategic resources within their collection range.
Dedicated Mining Starbases are still the best for resource-harvesting, of course. However, you're no longer forced into situations where you must choose to build an Economic Starbase that boosts your planets' abilities, but at the expense of no longer being able to mine that juicy source of Promethium nearby.
I also gotta say, I'm liking the Ideologies more and more. They're fairly powerful, and definitely add some flavor to your empire. They're a little like Traditions in Stellaris, which is not a bad thing IMO.
In addition, I'm discovering that you really cannot ignore settling the minor planets (Colonies) that "feed" resources to your Core Worlds. It's tempting to just go right for the big juicy planets you come across, but if you do, then they won't be nearly as productive. There's certainly still a "colony rush" (just like in most space 4x titles), but your priorities for colonization aren't going to be quite the same as they are in other games.
My final comment for now: I love the way GalCiv4 has implemented Citizens as a mechanic. Your Core Worlds generate new Citizens at a certain rate, and these Citizens are what you truly use to expand your empire.
When you finish building a colony ship, you must load a Citizen onto it; and that Citizen's stats (Intelligence, Social, Diligence, Resolve, etc.) will determine, to an extent, the stats for the planet (whether Colony or Core World). A Citizen with a high Intelligence stat will give a nice boost to a planet's research, a high Resolve stat will boost a planet's ability to resist invasions., etc.
You must likewise load a Citizen onto constructor ships, and that Citizen's stats will partially determine a Starbase's defensive ability, mining output, etc. It's a pretty cool system, and I wouldn't be sad if other 4x/grand-strategy games in the future were to adopt something similar.
I believe I read in one of the devblogs that the new combat system is due to be implemented during EA, so there still is hope.
https://forums.galciv4.com/516719/galciv-iv-supernova-dev-journal-3---battle-viewer-and-ship-behavior-improve
https://www.galciv4.com/article/517359/galciv-iv-supernova-dev-journal-7---whats-new-in-supernova
I realized that after I posted, but it doesn't matter: Combat is still going to be crap, regardless of whatever "improvements" are made. I've generally enjoyed the GalCiv games, but combat has always been a pile of rat turds, and this game is -- and still will be -- no exception (sadly).
Including the pointless Battle Viewer -- which you can only watch *after* combat has already taken place -- merely adds insult to injury.
