Dave - Mike covered pretty much anything I had to say, the only thing I'd add is that it sometimes pays to deliberately 'overexposure' a version of the final image just to make sure some interesting piece of detail hasn't been lost that could be recovered, at least in part, without sacrificing the whole image.
Also, I don't know if you are aware but NIK have a youtube channel at
http://www.youtube.com/user/NikSoftwareLessons which has some really great content and a quick search on youtube will show loads of other contributors - you can pick up all sorts of odd little gems from them.