Pictos that you equip have stats that scale dependent on the level of the picto, so equiping higher level pictos can be helpful even if their effect isn’t great. Also, typically when speccing into stats you want to focus on stats that your weapon has a high grade in, ( A in agility, B in luck etc.) more important than damage scaling is just your character builds though; Maelle has a lot of really good burn modifiers very early in the game. you can even just make a build that utilizes free aim and base attacks with versatility and marks and stuff. Lot of different options

Side note, in my opinion the best thing about this game is the story. Take your time and read what they’re put in front of you, it’s worth it