What is the max level in Alvastia Chronicles?

Could you tell me, what is the maximum level that a player can reach in the game Alvastia Chronicles? Is there a cap on how high a character's level can go, or is it unlimited? Additionally, do the benefits of leveling up diminish at a certain point, making it less worthwhile to continue grinding for experience? I'm curious to know if there's a specific strategy or approach to efficiently reach the max level in the game.