I've been meaning to get around to this Alpha for ages however I've been between ISP.
I was surprised that everything ran pretty smoothly without many bugs but I see that there have been a few patches. I like the new tax sphere, I like how research is divided up. I was never a fan of the technology tree in GALCIV2. I wish that when you were in the negative that you could see that easier. The money counter does go from white to orange but I think a flashing red would be easier for those of us who don't check it every turn.
I hate ship building when it comes to the look of designs(but love designing them from the specs point of view) but I found this ship builder far easier to use and really got into it.
I really like the way the ideology system functions and look forward to see how that really comes out.
So far so good guys keep it up. 
-Cyrinno