Nuclear too early, too cheap or too strong?

Well, that humans do that too and better became a side aspect of the Thread, but you are correct, human enemies could focus solely on nukes and defense. Thats one of the reasons i dont play against them for the most part.

But the problem stays at it is, nukes are not something that you build and have to use the moment it gets ready. It is very flexible, u can use it for comsniping, portaltargeting etc. etc., while anti nuke launcher are downright wasted money if he doesnt shoot a missle straight into it. The Area it protects is small, so that u need a high amount of anti nuke launcher to be halfway safe

The AI targets by the following rules:
Commander first, if position known.
Halleys (and possibly catalysts). Or other high Metal Value targets.
It seems smart enough to avoid heavy Anti-nuke cover or break through it using salvo-fire.

The commander should have overlapping anti nukes protecting him ideally. As he is the primary target.
Otherwise you want to guard your factories, and T2 popwer production and nuke launchers.
The AI will nuke you starting with hard difficulty. Unless you are able to really kill them fast enough, they will try to break any stalemate using the nuclear option. As the fight drags on the propability of the AI firing a nuke approaches 1.