I vaguely recall getting high scores in the past, but I don't know what's more important. Time? Resources? Units? Structures?

Longer games have lower scores, but shorter games don't necessarily bring you high ones. For example:

I don't think you can do better in any respect, but I'm sure I've seen higher scores. Does anyone know what's the preference?

It's a factor of units and structures destroyed. Those lost don't have much effect. Spice is responsible for a smaller part of the score:

Time is mostly inconsequential: