Yeah I completely agree. It's very obvious resists + shield hamper magic's especially in beginning. I don't recommend magic for the first play through as it is far more tactical. I am currently rolling my fourth play through with 3 mages and a summoner/hydro. It sucks to have to sometimes respec for certain fights because both the magics you have gone into are high resists.
This is why I've avoided magic builds. Either you have to re-spec/skill swap every single fight OR you have to waste a ton of points in Memory. You've also got to keep spare weapons that have the element type you want for max damage. For me that doesn't add to the difficulty of the game, it just makes managing those characters annoying. Those closest I got to playing with magic effects was my archer that utilized the various arrows as the tactical situation warranted. It's probably the most versatile build in the game being able to do killer magic and physical damage.
