When you work on your eyelid morphs, make sure that you have the eyeball object in a background layer. While it is the nature of morphs to change linearly, I've never had a problem with the eyelid morph entering the eyeball at. 50% when creating morphs for my figures.

While making smiles you need to be able to sculpt the lips and cheeks without damaging the underlying teeth. In Zbrush I'd mask the teeth and tongue (provided that this is part of the head).  You should keep in mind that a smile doesn't just affect the lips.

You can open a mouth by selecting the jaw, inner mouth and lower lip and rotating the selection in the side view, with the "hinge" of the rotation at the back of the jaw just like real life. Then you'll need to smooth out the horribly stretched polygons on the cheeks and re-sculpt the area. This is a breeze in Zbrush, though the first part of this task might be easier in a conventional modeler.

I've wondered sometimes if it would be possible to create a chain of morphs in Poser and assign them to one dial. That is to say, the body parts effected by the morph chain would be influenced by morph 1 from 0 to 25 on the dial, morph 2 from 25 to 50, morph 3 from 50 to 75 and so on. This might be a way to compensate for the linear nature of morphs, but I don't know if it would be possible in Poser.

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