I typically go for:
Map: Gigantic or immense. I like to play against 9 major races.
Habitable planets: Occasional or common.
Number of Planets: Common
Stars/Anomolies/Asteroids: Abundant
Scattered star density.
Minor races: 8 w/Tech Stealing off.
Tech Speed: I set it on Very Slow most of the time.
I have not developed a preference for Tech Trading, Blind Exploration, or Mega Events yet.
Here's what I generally do with these settings:
Playing as the Korx, I select Federalist as a government type and put my 10 points into Military Production, Sensors, Creativity. I do this so that I can use freighters as exploration ships. The risk/reward of this involves finding a minor race early. I have discovered that it is bad to send 11 freighters to the closest major race, as they will use the trade money to out-colonize me. If I can find a minor race, I set a rally point on their planet and use the Governors to automatically send all the freighters to that location. By the time all 11 freighters have reached the destination, I usually have a very good selection of habitable planets to go after. The trade money lets me colonize at 99% production for quite a while, and I invariably end up with a LOT of planets. Later, I transition most of the trade routes to major races. I then turn on the minor race so that I can get all those resourse bases that they used MY trade money to develop. Gneeheeeheee.