How come the death scenes in King's Quest VII weren't as graphic as other Sierra games?
The King's Quest games were always more kid-friendly than some of the other games. I don't think seven is any less graphic than the others in that series. But if you're talking about something like, say, Quest For Glory or Gabriel Knight, they were a little more adult than King's Quest, and thus more violent.
It would probably look well out of place in a cartoonish game. Even in the scope of cartoons, it's more Disney while many Sierra deaths are a lot closer to Warner Brothers.
I got the sense with KQ 5 that they were so excited to finally have the capacity for more developed story/dialogue/characters that they rushed out one draft and didn't stop to make sure all the characters had a purpose (or the dialogue and voice acting were particularly good). KQ 6 was a huge step up from KQ 5, plot-and-character-wise.
Since Valve/Vivendi owns Sierra, why haven't the old games been put out on Steam? Do they just not see a demand for them, or is it a rights issue with the various creators?
Well, Sierra now belongs to Activision for starters...
Some of them are; a Kings Quest package and Space Quest package are both available on Steam.