The AI does two things that bother me.

It spams the light frigate.

It actually uses seige frigates in very early game.

I don't care so much about the use of spamming light frigates. It's actually not a totally useless strategy, but stop making it use seige frigates. The CPU is easy to beat because it let's precious slots be taken up by seige frigates, ships that are easily destroyed and require too much investment.

The computer attempts to send five or six at your planets while you're not looking. Make 2 or 3 turrets at every world and they just run. Take the Seige part out of the CPU at least until latter stages. The way it is now, the comp isn't too much of a threat.