I'm about to run a Vampire: The Requiem game using the Requiem for Rome setting. Naturally, this means I have a whole universe of research available on Ancient Rome. What I want to know, my fellow GMs, is how much research is too much? When do you stop photocopying sections about Gallic dress styles and the Roman public education system and just wing it? On the one hand, this shit is downright fascinating, but I've done this all long enough to know that too much material just makes your head spin and most of the time the players don't give a shit either way as long as the story's interesting.
Especially those of you who've done more sandbox style games, what major points do you hit on in terms of fleshing out a place or a culture that come in most handy? Is having random factoids you can summon up at a moment's notice a good thing that both informs and enhances gameplay (oh shit, edutainment!) or in the end does it really just become too much of a pain in the ass trying to achieve authenticity that the game just falls apart under its own weight? I know a compromise between the two is best, but I was wondering if I should lean more one way or the other.