I'd say this is a pretty good first card.
You should definitely make it harder, as μ⑨ (Which I just now realized says 'Mukyu' >_>) said. The red bullets aren't dangerous at all as long as the player is at the bottom of the screen, and moreso the blue ones.
You could try adding another pattern into the mix - Even something as simple as a sunburst can make a spellcard more interesting to dodge.
EDIT: Actually, the red bullets do eventually reach you. Unfortunately, when they do, their speed and curved movement make them awkwardly hard to dodge.