Quote -
But what's wrong with building morphs off others?
I mean for example, I'm not going to do hours of morphing to get one phoneme, then repeat the whole process to get another similar phoneme - I'm going to start with one base open mouth morph and build all of them from that one.

Phonemes are in fact a great example of what not to do. To put it bluntly: phonemes are a stupid idea. I'll give you two reasons why:

Firstly, why make all those separate shapes when for 90 percent or more of your voice acting needs, combining just three morphs at the right settings - open, wide and narrow - will do perfectly fine?

Secondly, there's no such thing as a unique shape for most of the sounds we make in speaking. For many of the vowels for example, we have quite a range of lip shapes that will work, and which one you'll see in a speaker depends on the sounds that came before. If you use phonemes religiously to match sounds, you'll get an animation that looks extremely silly and not at all realistic.

Of course, you shouldn't believe a noob like me about the phonemes. Believe Jason Osipa instead. If you have some green stuff to spare, I highly recommend his book Stop Staring. It was a real eye-opener for me.

Back to reusing morphs: in general, it's usually a better idea to identify your basic building blocks. If you want one character with big breasts and small areolae and another character with big breasts and large areolae, it's much more efficient and useful to make just one morph for the breasts and one for the areolae, and then combine those to get what you want.

Of course sometimes it might be useful to build from an existing morph. But I'd bet in most of those cases it would be even more useful to look at what's different between the morph you already have and the one you want to build and make a morph for just that aspect that's different.

-- I'm not mad at you, just Westphalian.