yeah because everyone one loves killing someone important to the main quest, playing for 40 hours, and then realizing you have to lose 40 hours of gameplay or even start a new character becuase you can't complete the main quest
what you want is what I like to call bad game design
however I would like it handled a little more subtle than in oblivion. Let me kill every character but at least give me a heads up if I've broken any major guild quests or the main quests
I'm sorry but oblivion and morrowind were different in that quest lines interfere with each other.
NO unconcious anybody!
how would you know if you killed a house faction member unless you spoke to that faction?
there should be a feeling after you kill an NPC key to the story line that you F***ed up, but other than that, you kill at you're own risk. If you are alligned with a faction you should know who the key faction members are, and therefore you should know killing them isn't a viable solution to progression. I think gamesas has made it clear that NPC's repopulate, so i don't think that this will be a a problem (for the main quest anyway.)
I believe gamesas will make the most immersible and realistic game ever, and if you screw up so be it, there should be enough content to satisfy you for more than several years, what with havok behavior and an obvious implementation of dozens of creature animations.
prepare for the greatest game in history and take work off for a year to ensure maximum gaming xp. Not just saying this, I have been waiting on multiple RPG titles and this is well above my expectations.