So I guess an easy way to solve it is, if Toady wants souls in the game, he'll put them in, if not he won't. It seems like a topic for which inevitably there'll be 50 different viewpoints on, though it is fun to discuss.
What about if after a creature is slain, its soul comes out and is now a wraith, something like that. Maybe it only happens if they're beheaded or something.
Something that I wish is that DF would be more descriptive about what is happening in the game. During a goblin siege, you can see creatures dying and their limbs and organs turning yellow/red if you use the '.' key, but there's a lot of small details that you have no idea about, I wish that it were possible to somehow have more detail in the graphics or some textual explanations of the action or something.
There are souls in the creatures and probably a myriad of other details but there's no way to know the details of what is happening, which is kind of not cool; This is probably an unreasonable feature request, but what about having a command where what is happening within 2 squares of the cursor is reported in a text window or something, so that you can get a description of the combats or other things. This is the total wrong thread for it too