A long evening of gameplay, and much too much fun.  Here are some reactions.  All in all, there is some impressive progress!

I started with 3000 credits.  Change notes said 1000.  I see in another post this is part of Custom races, which I was using.

My custom faction carried over.  Thanks!  My starting Scout ship for my custom race, "Everybody Else", is now named a "Vision Giver".  That is an interesting and creative touch. My starting Colony ship is Colonizer-1.  (The ship designator for Everybody Else is the acronym "NOT A".  Therefore I start with "NOT A Vision Giver" and "NOT A Colonizer-1".  I am strange with naming.)  It's a little surprising and immersion breaking starting with ships I can't build.  That was an issue in GC2 that I thought we had gotten away from.

I noticed that class 0 planets are hollow in the highest strategic layer and you can see the background through them.   I amused myself by moving the map around and centering stars inside the planets.  I said I was having too much fun.   It is also true for the icons for unsettled planets, but you have to look for it.  This may have been true in earlier versions, but I don't think so.

In the shipyard assignment dialogue box, I like the little icon that shows a planet is sponsoring a shipyard.  That was a confusion at times.  Polish like this will help make this game great.

There is still an issue with UI sounds.  If I try to set the volume to make end of turn audible, the opening noise of many dialogue boxes is some loud white noise thing that sounds like a single burst of artillery fire.  If I have both SFX and Music disabled I still get some sounds and I get a lot of clicks where sound would transition if it was enabled.  The worst seems to be during reload of a saved game.  There are several such transition clicks in a row and it seems to correlate to when it is painting the planets in the planet list.  (My slower system sometimes lets me see paint sequences as part of a lag.  I am waiting for a memory upgrade on order, but in the meantime, this is almost an advantage.)

The AI is definitely waking up from hibernation.  Two races have declared early war on me for being so horribly obviously weak.  They haven't carried through on it yet, but we'll see what happens.  Update from first notes:  I talked the Iconians out of it finally. but the Drengin are being stubborn.  However, my emergency military build up is finally about to start delivering.  It is late here in the Rockies and I want to wait until I am a little more conscious before the shooting starts.  I wouldn't want to miss any gratuitous violence.  It definitely adds more fun to have an active opponent.

My 8 gig system seems to be doing a lot of disk work that I don't recall in earlier versions.  It seems like it is paging in and out a lot more, especially if I change major functions, like switching to diplomacy or the shipyard.  This iis the same general Immense settings as all my other games.  An exit and restart seemed to help for a while.  I have all my settings to standard values I have seen in the threads here and there.  If anyone else with middle-low systems is seeing new lags with this version, speak up and let's look for a correlation.  Otherwise, it is just me and my system.  Probably just me somehow.