Core ships better than what I can build in the beginning?

Yes, the starting core designs are a bit unique, which is why players can't technicially upgrade the designs, but later in the game you'll be able to trump the core designs with your own

Also, the core designs should be a bit more expensive than your custom ones, so there is that penalty for their extra power.

Man, I try to add two colony pods to my new starting colony ship and I am pretty much out of space on the hull (I have space for 1 life support module). As a result I have a ship that costs almost the same as the starting "core" colony ship, is SO much slower and lacks any real range in comparison.

Unless you choose a race that starts with minituarization technology (like the Yor or Thalans), you won't be able to do much with your initial designs because you just won't have enough space. One exception, however, is the Scout design. No matter who you play, you should be able to upgrade your scouts with more engines, sensors, support module, etc. (Basic design comes with no sensor modules, which makes little sense on a scout)

I find the scouts pretty useless--generally the first thing I do when playing with a hull style I've not used before is design a sensor drone ship (varying in speed and range by map size, but always with tons of sensors... the Yor ones can get up to 21 parsec radius at the game's start).

IMO one colony pod is sufficient and the additional speed or range is worth leaving 250M colonist at home.

Scouts are good in big map games but a usuall a waste in small map games and definitely a waste on a tiny map.

It is a flaw in the AI (at least at normal) that they will build numerous scouts in a tiny map game when they should be building colony ships

Core colony ship only has ONE colony module on it.. the OTHER thing that looks like a colony module is a dummy module added in... you can create a colony ship that has the same colonist capacity as the core ship by just placing ONE colony module.

Rob

I was able to design a pretty effective colony ship earlier on (about 12-15 turns into game - side note I've only played about 45-50 turns). As the Terrans I researched propulsion until I discovered Ion engines. I then designed a colony ship with one colonist module, two Ion engines, and 2 or 3 basic life (can't remember the exact amount) support units. The ship is about 3x as fast as the core colony ship and has about 3x the range.