OrgLaw V authorises "election laws", even though they're not mentioned in OrgLaw VII.3, so OrgLaw VII.3 cannot be a definitive list. Since OrgLaw IV both mandates that parties win seats, but that individuals hold seats and vote in the Cosa, the question of how parties assign seats to individuals must come under election laws.
And that's excluding the whole question of whether OrgLaw VII.3 is a list of "permitted topics for legislation" or "topics on which only the Ziu may legislate, not the provinces". If you believe the former, it doesn't actually include (for example) criminal law. Half of El Lex would disappear overnight.