So it can be kindof confusing that the plane that you have to draw on is not orthogonally vertical, but instead a projection from the headset direction. This basically means that if you are looking at a different direction, the spell no longer can be cast the same.
My idea to help with this (other than just making it always orthogonally vertical), is to have an option to show the visible plane somehow when casting a spell. (like a mini roomscale wall that is in the proper direction). I dont know what would look good here and not detract from the aesthetics of the game… but i’m sure something that works this way could exist