It would be cool with familys that really worked perfectly with every kinds of stuff. The 'qualifiers' in mmf was pretty buggy (or at least the 'groups' in tgf was, haven't used the qualifiers very much.)
Edit: Think it will be in the nex trelease? I've got an awsome game idea, and i just need the familys to work to get started on the first full game made with construct that i know about! (eccept the billiard thing, but Deadeye aparently didn't think it was a game)
I uploaded a simple demo of the concept to the Creations forum!
I don't recall any major bugs with the qualifiers in MMF, except that people were using them incorrectly in object behaviors. People would mix up their qualifiers and end up sending actions to them that didn't match the object type.
That's more of a user error than a bug, though. Still, CT decided to bar qualifiers from behavior events to "make it easier on people." Pretty stupid if you ask me.