The most difficult thing about drawing a rune is keeping the end of your wand steady. If we could draw with something shorter, say… your fingertip? A magic thimble? People might find their spells are easier to draw accurately. The slightest wobble won’t make the end of your finger sway out of place like a wand.
Drawing faster reduces the wobble
Or draw it smaller and faster to get over the wabbling.
Or draw it excessively large so the wobbling doesn’t effect the shape as much.
casts fireball 2 the same size as a kelpie
Let me just say your spells don’t have to look nice, I promise