This is pretty much exactly how I see it, except I called it "social skills" instead of "extraversion", and I hadn't tried to break it down in such a detailed manner. "Gregariousness" is probably a better term, like Ashton said. But yeah, it's pretty clear from my observations of Real Life that STs and NFs both tend to be more socially skilled than NTs, but less than SFs (and obviously Extraversion plays a role).

If I had to break it down, I speculate that it would be something like:

INTx -- ISTx -- INFx -- ENTx -- ISFx -- ESTx -- ENFx -- ESFx

Not entirely sure of the placement of ENTx and ISFx there.

And like others have said, subtype plays a significant role, as does the setting. A geeky C-LII will be much more outgoing at something like ComiCon than a businesslike N-ESI in the same setting, who may be somewhat weirded out by it all.