I've now played many games in Ultimate Team and Seasons.
In my opinion, the game is currently well-balanced.
The game has developed very well since its release.
The balance between offense and defense is now okay.
My opinion on the AI-Defense:
The AI-defense is basically okay. ✅
It could behave more intelligently in certain situations.
Goals are often scored through the middle, and gaps are most easily created in the center.
In its current state, it's best to rely on the AI-defense in FC 26.
Selecting the center backs and defending/tackling with them is a big risk.
If you programmed the center backs and manual defending to be as effective as in FC 25,
it would be possible to rely on manual defending again!
In my opinion, only then could the AI-Defense be weakened!