It would be nice to have the functionality on the Work List to separate approvals into their own list or some way to indicate that a user can review a proof. Tasks can be assigned to multiple people, but two of the three users could just be reviewers. Having the approvals separated could help keep the reviewers from reviewing the proofs out of order or keep the approvals from getting lost amongst the reviewer's other assigned tasks. Really, it would just be nice if the Work List had more customization.
