That won't work (if I got you right). A package is either version controlled or it isn't.
That's not quite right. With
user security, you can allow some users, but not others, access to the version control facilities.
But that's a moot point, really. I discourage the use of external version control (
edit: it's called
manual version control these days) in EA because it just doesn't work all that well. Mainly due to the fundamental nature of version control.

I am a great fan of the
Reusable Asset Service, which can be used to good effect in scenarios similar to the one you describe. With this, you store reusable models in a "storage", from which they can be retrieved to different projects. This way, there is a published approved version of a model which doesn't change (until users with the right level of access decide it should), while other modellers (such as your business users) have access to local copies which they can use and even make changes to without breaking anything in the published version.
The trick there is not to limit yourself to a single project. If that's your thinking, you're missing a large piece of the EA deployment puzzle.
Finally, I wouldn't go down the EALite route. I have no inside information, but my feeling is that Sparx considers that a bit of an ugly stepchild. They won't drop it because they don't drop anything, but I'm pretty sure they'll be allocating far more resources to the webby side of things than to EALite.
HTH,
/Uffe