It would be cool if they added some personalities to companions. For example, a character may be be extremely afraid of spiders, so if one attacks you, he/she might run away screaming. Or if you are approaching a large group of bandits, he/she might say "We are a bit outnumbered, I don't think it would be smart to attack them." Another example is being drastically outnumbered in a fight, and the companion saying "I'm out" and running away. However, I'm not saying all companions should be cowards, just the ones that are weak/don't like you that much. There could be giant Nords that aren't afraid of anything or people who really like you that may try to defend you to the death.
Also, I don't want them to be endlessly following behind you. If you stop near a cliff, they may walk away from you to peer off the cliff. Just little things like that that will make them feel more alive.

I feel like this is one of those things that's just hard to code for. You ask for the guy to look over the cliff and maybe make a comment, but do you have him make the comment if you're in battle? If he's already done it before? If you have a different companion, will they do it too? Will they say the same things? I love the idea, but I feel like it's just one of those things we might never get to see due to issues like that. Now, one thing I think would be neat that might be close to this, would be to have a follower say something when you're in a certain area or something like: "Hey, I grew up around here. There's this cliff I used to go to at night to watch the sun set before my village was destroyed. Would you mind if we go there sometime?" Then they put it on your map and when you get there they walk to the edge and look out like you said. I think things like that would give them some depth. I love all of your ideas by the way.

fallout 3 and fallout nv did this.

Ive never used a companion in Oblivion... they are weak, feeble, stupid and noisy. I would find myself inclined to kill a companion myself than go into a fight with an idiot.

Same here, actually. I never used a companion in Fallout 3 either. I'm using two companions in New Vegas, though. I think it's because they can't die. I was alway stressed out that my skinned dog would get lost or killed in Shivering Isles so I never actually used him.

It might be too much depth at least for this console generation. You have about 9GB of space on a single 360 disc and all that audio would never fit,and if you go by blu-ray standards it might still not be enough room. Unless you go with compressed audio then that might not be such a preferable option. I also enjoy the action part of the game more,so stuff like that would be wasted on a person like me. Well maybe not wasted but one time would be enough,I prefer to avoid virtual emotional baggage.
Edit:You hit the nail on the head there Nero. Having companions die on you svcks!