A couple of minor things that have actually been haunting this for a long time that I kind of assumed would get taken care of but haven't so far so I figured it was time to say something.
1. With the exception of the very first one, all the techs that are meant to lower the cost of ship defenses actually raise them. Namely "Low Cost Shield Systems" (which also seems to have a rogue decimal point), "Low Cost Shield Generators", "Master Shield Assembly", "Low Cost Point Defenses", "Counter Measure Manufacturing", "Master Point Defense Assembly", "Low Cost Armor", "Armor Manufacturing Focus", and "Master Armorers" all raise the cost of their respective defenses instead of lowering them.
2. The game needs a couple more points of memory assigned to tracking your credit total. As it is, it is way too easy, especially in late game to overflow the money total and go deep negative and with a developed economy you can actually repeat this every ten-fifteen turns or so. Before I figured out "modcredit", this one in particular made the game very frustrating to play late game.
That was all, just those minor things.