Sorry, a suggestions I would like to ask for is the ability to import custom expressions which also include posing of bones?
An example is like the image i just uploaded, showing the same char with the same expression dialed in blender and DAZ respectively.
the expression in blender was done via Custom Morphs
If it is at all possible, would it be possible to import expressions using the duf file?
Bone pose morphs are imported - all standard morphs except for the FACS ones consist mainly of poses, and in your example the jaw bone is rotated. However, only rotations and translations are supported unless you enable the Scale Morphs (Experimental) option. The tongue is moved by scaling it, so normally this only affects the tongue.
The option is experimental because sometimes the tongue pose is wrong. I fix this by compensating with some of the tongue morphs in Face Units, especially Tongue In-Out.