Well, I went through the entire beta without building a single one, I was too busy building mining star bases to grab those resources you really really need now.

But recent patches have added back some boosts that were lacking in the beta, so that econ star bases can now (again) boost manufacturing, research, income, and trade.  I still don't see any approval star base modules though.  I'm still going to favor mining over econ, I think.

With the shortage of resources, who can afford to beef up the econ bases?

I can't get over having to pay out resources for a shopping center when you also pay cost of building. There should be a full price and a resource discount deal.

On key planets: Yes.  A must build.

But not for all planets.

For the most part (especially early on) you are better off just looking for some asteroids. Also potentionally saves you money on life support.

The economic and trade modules still seem to be running on pre crusade numbers, so they are worth it. But for manufacturing and science? Only if I had literally nothing else to spend my ressources on.