Aizen made a wrong count and all the espadas numbers are fake. the numbers doesn't mean anything.
THE REASON WHY STARK WAS PLACE ABOVE BARRAGAN IS TO WATCH OVER HIS SUSPICIOUS ACTIONS, BECAUSE A WEAKLING LIKE THAT COULD NEVER STAND A CHANCE AGAINST RESPIRA, it slows down movements to nothing and rots you away immediately. also barragan rots away kedo hako and cero.
ESPADA # 4 IS MORE POWERFUL THAN HALIBEL AND STARK; UNLESS HIS SECOND STAGE WAS WEAKER THAN BOTH OF THEM FIRST STAGE or lord aizen didn't want to start a conflict between is army so he didn't make any adjustments in is top 3 espadas levels. they got trolled really hard especially stark total failure for been #1. BUT BARRAGAN IS THE ONLY ESPADA THAT CAN TAKE ON ALL 8 ESPADAS AT ONCE IS RESPIRA IS TOO GODLY IF THAT TOUCHES YOU IT EATS YOU AND AGES YOU DOWN TO BONES. after all he's king barragan of heuco mundo, dont you all agree?