I fail to understand what the reason for your frustration is. this is an Early access game. If they were to implement every available spell for levels 1-6 or 1-7 they would have to spend more resources balancing them right now for us, instead of working on the story,dialogue,narration, world building and other much more important aspects of the game.
That's 100%, I guess I wasn't clear. What I meant was "why not just let higher levels be available, with the understanding they'll be janky?" It would be totally reasonable to say "for EA, we're only supporting up to level 4, so please no feedback on anything above that, but higher levels are obtainable, just know they're not finished"