Here's something I noticed recently that I really like about the game. As I've built up a handful of custom factions, I play against them regularly now. And for the first time I noticed the AI building a unit that I had designed when playing that faction. Nice!
I'm going to have to make a concerted effort now to keep the list of units clean, and not retire all the obsolete ones as the game goes on, just so the AI has access to them all.
That said, I believe in some of those games I "retired" some basic early units like Spearmen, Archers, etc....does this mean the AI can't make those early units? That would be bad.
Gotta have a "props" thread every now and then.