Town Portal and Lloyd's Beacon are Water Magic Spells that will help you move about Jadame. They'd probably be worthwhile if all they did was to free us from the transportation schedules, but they do much more.
These spells cut transportation time to zero, making it possible to take advantage of various resources throughout the land before, during and after combat. You can visit various Well and Pedestals to boost your abilities before engaging your enemy. You can make a quick trip to an Adventurer's Inn to change your party composition. You can rush to a Temple to heal and cure condidtions. At Grand Master ranking you can (ahem) make a strategic retreat in the midst of overwhelming opposition.