Actually takes me back to my (incoherent) point re: the corot painting - in that the obscurity of the faces in these unfinished works makes them more mysterious, and therefore more universal (not the right word - i suppose i mean that the figures in that delacroix, because faceless, could be any of us)
The ultimate examples (?) of the unfinished work expressing (even if inadvertently) something profound about the mystery and transience of human life are Michelangelo's captives
Which also express michelangelos' preoccupations with the spirits struggle to transcend material reality