saveStatus and saveIdentity are the only commands that work in MP.
My mod (Sinews of War v1.0) used those. I am working on SOW v2.0 and plan on introducing several MP campaigns after the core files have finished.
Check out the site in my sig. It has the v1.0 files and feel free to look through them. They are a little dirty though. Version 2.0 is coming out (very soon) and I am currently working on a website for it. It also uses CoC Network Services to handle client/server relations better.
Your idea is a good one, but I would like to point out that once you save a status anyone who logs into a mission under someone elses name has the ability to muck up that persons save. There is no security there. Just keep that in mind. I have had nightmares trying to figure out a security feature in my own mod, but have yet to come up with a quick and decent one.
Added: I forgot to mention that your tool is of great interest to me. Once I get my site up, I would like to collaborate w/ you on it and possibly others