The default pace, Classic, may provide a game that feels rushed. The research tree is completed soon.
Accordignly, the default turn limit is set at 500. But when that comes, you may well feel that you are not even half done with the galaxy.

Taking a look at the advanced settings, it appears that the Classic pace includes a Fast population growth. Setting it to Normal (which then makes your pace a Custom one, a bit surprisingly) makes for a more ponderous game.

Taking into account the names of the settings, it might be that the developers provided a fast experience for people who felt restless, or for galaxies of size small or medium size, while hiding an all-normal mode with a different rythm for those who like more epic games.

So, what do you think? and what do you like?

My favourite game so far was of epic proportions. Largest amount of systems, and gradually conquering them all. As a little twist, I'd conquer each race until they had just one system left, usually that of their home world. I'd then destroy, capture or colonise any other planets in their home system, and effectively blockade the gates out to prevent them expanding again.

Once I'd done that with all the races, the end-game would depend on what sort of 'victory' I wanted. Sometimes I'd apply the 'coup de grace' and just wipe them all out on a whim :)