As a BI developer with a handful of DBA responsibilities too and having been paid well under the market rate for the last 4 years I would love this! Though I know several people, particularly in my last organisation who would be less comfortable.

The largest problem is probably scalability. My wife works for the ambulance service, and here in the UK they have a similar pay banding system where you move up through a band and the band is based on your skills and responsibilities, but there are problems with ranking dissimilar roles, eg HR and Paramedics (for those that are interested HR fairs much better then paramedics).

I'm not sure if there is an ideal solution to this problem, but openness must be better than keeping everything secret. After all, MPs over here are finding out what a pitchfork looks like from the sharp end after a lot of financial secrecy!!