Hey fellow Final Fantasy X explorer! When it comes to sphere grid progression, my tip is to focus on unlocking key abilities first before branching out. Make sure to use sphere levels wisely to maximize your character’s potential. For side quests, don’t miss out on capturing monsters for the Monster Arena or completing the Celestial Weapons quests for powerful gear. As for character builds, experiment with different paths on the sphere grid to customize your party members to suit your playstyle. Happy exploring!