Being able to change (e.g.) the theme for option A independently from optione B and C would actually annoy me to great affect. If I happen to change it, I would have to do for every option. However, this could be fixed by being able to "link" the presets together, so they all look the same.
Being able to change the (e.g.) face for each class individually could mean that each class is a different person. Which means every player can either be 3 different persons, 3 twins, or just 1 guy who is able to play each class.
MUSE has to decide wether they want that or not, may it be as good for personization as it is.
Generally, I support the idea.