One thing that might not be obvious is that planet specialization is very important. That is, pick what you want a planet to "be" (manufacturing, research, or economy world) and build the world to be good at just one thing. The governors should do a good job of this, but I haven't tried them (I enjoy planning my planets myself too much) so I don't know firsthand.
Little tips:
I almost never use the global production slider, unless I really need something done fast.
If you've encountered any minor races, trade them your tech for credits. Easy money.
Unlock some diplomacy tech and build some embassies, if you need your neighbors to be nicer to you.
More population = more production, but keep morale in mind! Low morale hurts production, and high population lowers morale.