Well, I can confirm, the Parthian Head Covering is working as expected. Perhaps it is possible to get the parts beneath the chin and around the neck closer to the body.
I'm not so sure whether it is a good idea to upload very experimental assets, especially when they leave traces in the error-log, i.e. are not working (e.g. rename the files of the spartan worrier from XXX01 to XXX1). This might confuse Newbies. BTW we could ask Joel for an experimental section on contributions page. There you can upload your stuff that needs rework and ask for critiques.
My artistic skills are very limited, so I'm not sure if my work flow is helpful. I start of with modelling by using background images or directly on the base mesh. Then I do the fitting, to the appropriate base mesh with helpers depending on the desired target (male, female, unisex ...). (Making good textures, normal maps, bump maps... is another thing

) Next step is defining good vertex groups often by hand. After export to MH the testing process starts especially under extreme conditions (age, weight, hight...) -> re-fitting, re-do the vertex groups, delete-group... This can be real pain i****.
Mostly I'm done once I can do a Collada export from Blender.
Not sure if I get the point here for a good modelling work flow. You can export almost everything to Collada, so this condition is always true.