Interesting, but my own concept of vitality/wounds is best served by limiting feats and effects to only dealing with one or the other. For example, cure spells can affect either vitality or wounds (at half effect for wounds), but never both. Heal, however, fully cures ALL damage, so it affects both vp and wp.
If you run into any other design considerations regarding vp/wp,
DungeonmasterCal, send me an email–or if you start a thread on the subject, a private message–and I'll let you in on ideas I spent hours or even weeks poring over.
Remember the name that is
genshou when it comes to vitality/wounds in D&D: I'm the only one I know of here on EN World who has been using it since 3rd Edition came out, and thus I've worked out most of the wrinkles. Most.