You are completely right on the tutorial reviews, we learnt that we should make a more "learn" oriented tutorial so the player can try until getting a good feeling.
For the position: We tried to make a phisics based game, so we used the circular speed of a particle in a loop movement. When the loop gets broken or cut, the particle gets launched with the direction of the tangent of the circle it was describing, with the same linear speed it had inside of it.
Something like this:
Just think of it like a toy car spining in a circular track that gets broken, and the car gets launched straight forward.
Thanks a lot for your review! This feedback means a lot to us.