I'd think there would be a market for that.  As a matter of fact, there SHOULD be a market for that.

There are far too many "dialspin" characters out there.  I refuse to purchase dialspin characters.  Why should I pay someone for producing something anyone with a digit on their hand can produce? 

1,.04,.03,1,-2,-.04, etc... = "ZOMGZ NEW KARACTER!"  ain't really what I call significant.

As a spinoff from another project, I started working on some custom face morphs as well.  What I think is really needed is a pack that covers every major facial group so that users can have not just an alternative to Morphs++ but a complimentary package that has the possibility of giving them tools to produce "unique" looking characters.  I've d'loaded a couple and even purchased one.  I have been less than satisfied with every single one.

That's the problem with Poser... Morphs++ only goes so far and most of the morphs are not centered around producing faces with a lot of variety in them.  Moving dial x to .00003 doesn't really help very much.

Put your product together, make sure to include some good features that focus on producing unique looking character morphs that work well with Morphs++ or by themselves, market it appropriately and you're sure to generate some interest.