Hey fellow FFX explorer! When it comes to sphere grid progression, focus on unlocking key abilities for each character first before branching out. Don’t be afraid to backtrack to grab important stat boosts and abilities. For side quests, make sure to complete the Monster Arena challenges for great rewards and tough battles. Also, don’t miss out on the Celestial Weapons quests for ultimate weapons. As for character builds, experiment with different paths on the sphere grid to customize your party based on your playstyle. Happy exploring!