If Mi'aro dies, by his laws, an emergency election is held a month later (Tirahnys has no president) with Aidan (or an associate) as candidate.
Also by his laws, only HIS party can be voted for.
This is how Alexis Flamberge became president, but her first act was to have things go back to pre-Mi'aro times, with Ilina back as president.
How Mi'aro got so many twisted laws through is crazy...
(*cough Boris Johnson and the Conservatives cough*)
Wait, this was before Serenity fights her in Lunar Shadow, right? Also assuming that the whole Myst Zone arc was canon, doesn't Ilina die in the Brainwashing Machine?