I would say that this is one of the surprises you have set up. Of course most of the other none seated clans could show up. The Uzumaki clan, based upon chapter 34;
can be represented by Sakura. It wouldn't be suprising if Sakura's parents return to cast their vote. If they can't, since at least in chapter 4 there were other Haruno families ("Our bloodline limit, of course," her mother huffed. "Inside you, and inside me, and inside your grandfather and you uncle and your cousin, there is a second 'persona,' if you will.), one of the other members could cast their vote, acting as a proxy or taking over the seat since Sakura's parents now intend to continue to live in Blossom.
I suspect that there is no law against relatives of Naruto voting. First off, desaix only said that "Naruto ineligible to vote as he is the designate being voted upon" not that any of his relatives; Sakura, her parents, and now at least part of of the Yamanaka clan (Ino's family, but not necessarily the clan leader/representative); were also barred. Also, since most of the stronger ninja (and thus potential hokage candidates) are probably members of a clan and a close relative of that clan's representative, it probably wasn't expected to be unusual to have a relative voting for a candidate.