in many more ways it would be difficult to implement and I don't think its ever going to happen.
I don't think so. It's a very straightforward system for basic planet development. It can only include like five or six structures/developments before it shuts down, just to get the planet started without checking on it every time I gather some change.
For instance; build extractors, build trade port (if available), build rafinery (if available).
Or with planet development; build extractors, build trade port (if available), build rafinery (if available), develop planet (that first planetary development, I forgot the name).
More or less everything else is too planet specific (location, endangerment, the need for fleet building capacity etc.) to be automanaged, but right now I need to come back to a strategicly insignificant planet five to six times to get individual structures built because I don't have the money to queue them all.
The planetary manager could also be custom so that you would be able to add structures like jump inhibitor and the likes.
Alternatively you could not have the automanager but would be able to queue the buildings/developments even when you don't have the dough ready - but you would still need the last two options I listed.