enemy knows!

yep, but not 100%

I just had a race with an opponent for a system. it was very far away from his point or origin, and he didnt seem to check any other systems along the way. He seemed as he know what go go for.

However

In the quadrant next to that on there were a better planet. Ok, I'm running the AI on the easiest level so that could be it.

Same again, I followed to different computer players race for the same system. The one that did lose found a _much_ better one in the quadrant next to it. It had two good planets, the worst one at the same level as the one they competed with.

The aliens know where the star systems are.

This is part of the plot. Humans are relative newcomers, the aliens have long since sent out unmanned probes over hundreds of thousands of years.

Good point, Brad
Very good.

wouldn't they have been colonized already? wouldn't our technology be behind theirs? guess it's a story thing.

If you read the story, humans went and made the millinnia old technology of stargates transportable. Before us, war and colonization was only possible by generation-colony ships.

However, the other races have known about each others for ages and have had all the time in the universe to explore.

Of course one could argue for the more realistic approach of the alien races knowing about the best systems in a certain distance from their home system, since it becomes increasingly more difficuilt to communicate findings across the vast distances between stars at light-speed only..

Just my two cents.

The scope of years is important:

The Drengin Empire, for instance, was a space faring society 100,000 years ago. They have long since mapped out the galaxy with probes.

But sending actual living things without benefit of a star gate (and you can't just beam a star gate out into deep space) into deep space wouldn't work out too well, especially with no realistic method of communication.