It's interesting to read your reactions to Scrivener, Hitch.
I was thoroughly impressed with the product, especially their interactive tutorial so you can really try it out properly and see how it's supposed to work. It's all so impressive that I'd really like to use it ... but I don't. I've tried a few times, but somehow I seem to spend more time mucking around, trying to get the tags and stuff all set up as I think I'll want, that I never actually get any writing done. I also think it's editor lets it down, RTF is not a good fit, they need something properly styles based. I haven't given up on the Scrivener yet, but so far it just hasn't worked for me.
I don't do detail outlines, so I come closer to the "pantser" side of the fence than you do. But OCD isn't biased, it manages to hit you whatever your style. (I have come to the conclusion that an obsessive nature is probably a prerequisite for writing). I make copious notes as I go: timeline details; setting and general background; great screeds of character history, from general details to scenes and dialogue. And because all this is developed and maintained as I write the main text, trying to make sure it all remains consistent is a lot of work. (I find having a separate place to get carried away writing background helps me to keep from trying to include it all in the main text - which saves me having to cut it all out again later.)
I did try yWriter a long while ago, but I found it sort of cramped and distracting for the actual writing part. Maybe I just needed to give it longer.
As a software developer I've had dreams of putting together my own solution, but I have enough trouble finding time to write as it is.
Dr Drib. Thanks for the links, even more things to spend time looking over ... just what I needed.