Having read the Fate/Zero novels i want to spoil the shit so bad for you.. but i'll hold back. I'll just point out some minor details that they didn't show(just small 'flavour' stuff, not spoilers).
In Einzberen Castle the stained glasses in the chapel have shown the scenes of Einzberen working on Holy Grail - just to show their obsession for it.
Archibald's title (Lord El Meloi) is a title for very strong and prominent magus i i recall correctly.
Waver is a pussy, that's a fact.
And guys - there is still one more master/servant combo left.
Waver's Servant is badass.