How to deal with lots of bad vassals?

[Yow!]

Ok, ive started as an earl (first game), and ive managed to become king of ireland, scoland holds 3 counties and the duchy of ulster title... im on my third king, and im having dificulties at dealing with factions being created even when my vassals have a positive opinion of me...

I give em money, i put the chancellor to work, i stay on the good side of the pope, but there is always a rebellious vassal coveting my downfall... what should i do?

[Artemis]

Strip his title and marry him off to a nobody. Obviously you can't do it too often but one opinion hit isn't a big deal compared to getting rid of a real thorn in your side.

[Denethor, Steward of Gondor]

Kill 'em all.

[eXistenZ]

Factions are a pain, cause even very happy vassals will sometimes join them. Keep them weak (dont give one guy too many counties/duchies), and groom your heir properly. The relationship difference between an arbitrary liege and a just liege is 20points, and hats just one trait.

Also, when your heir becomes king, bribe some powerfull vassals. You only need the big guys to like you, they provide most of your troops and money