I just played through a game as a Loyalist Tech against whatever the level is right before nightmare.

I am assuming the AI will get a lot tougher. It was frankly a joke playing 3 AI's. They built one capital ship and once I killed those for all three they never built another. AI's also seemingly never develop any systems outside their capital planet. Those were the only ones with star bases and those bases were not outfitted with anything but the basics. I also noticed none of them built rare mineral buildings so that may explain that? Very very very basic. I literally just had to build two starbases to hold any planetary well extremely easily. Looking forward to this being fixed.

Garrison recruitment center. THANK GOD. What a novel idea I did not think would take place. This is great for less micromanagement and does not impact your overall fleet supply. I sincerely hope this does not change at all.

Late game? TBD frankly based on what happens with mods (Distant Stars) and AI's actually building fleets/garrison centers. There was zero lag and I loved it for what it was I hope that does not change on huge maps with 10+ players and AI.

Trade Centers. I'm wondering if I missed it but towards the end of the game none of my new trade centers were trading anymore severely hampering my ability to generate credits. Anyone else have this issue?

Overall it's an awesome game thus far. Very excited about the forthcoming updates.