I agree with all the bascs of your proposal.
Having used the Dan Busarow online ballot, I know what you mean and I can
say that it works.
Nevertheless, to a certain extent the DNSO may be a more controversial and
litigious body than CORE, and maybe we could add a digital signature to the
process you describe.
In fact, each member can "deposit" its PGP Key (note that this may be
required anyhow for more "official" documents).
This will probably add a level of complexity without changing much (I think
that the frauds will be non-existent in DNSO voting), but will build an
additional level of confidence in the results that may avoid some
discussions and polemics afterward.
In other words, I think that while it is unlikely that we have frauds, it
may be likely that we have discussions on frauds. Digital signatures will
eliminate (or at least reduce) this.
Regards
Roberto