Do Mages make effective city-state rulers?

For added sword & sorcery feel, I’m contemplating on changing one of my setting’s city-state rulers, the corrupt King Balrazar of Yimara, from a level 11 Fighter to a level 11 Mage. Would the Mage class befit a city-state’s ruler well? Or is the Mage Sanctum stronghold and the Mage’s tendency towards burying himself in magical research make this less than ideal?

Also, would a Chaotic alignment befit the leader of a city-state which is not a complete den of evil (though its ruler may be quite nefarious)? Otherwise I’ll keep him Neutral.

Note that this is the number one rival of the players’ starting city, Harat, which is ruled by King Hardun, a Lawful Lizardman Gladiator (who led a rebellion against Harat’s Chaotic sorcerer-king twenty years ago and then installed himself as “king” after he put the sorcerer-king to the sword). Higher-level play may include a campaign against Yimara.

It very much depends on the mage’s CHA and proficiencies. A mage with Diplomacy, Military Strategy, and Leadership can certainly be an effective leader of a city-state.

Many of the high-level rulers in my own campaign world are mages or mage variants.