I'm sure you know the answer is that I can't guarantee it at all.
Anyone who guarantees an important result with simple shortcuts is a bad person.
If you follow the course expectations, you will improve and acquire new levels of clarity, control, and fluidity. Certainly! Your ideas will improve, and you will improve.
My advice is to enjoy the journey and just love what you do. Approach it with passion and conviction, be regular in your work, and do it for the love of music. We have one life to live, and your relationship with the music and the process matters.
Aim to be as good as the great composers/arrangers, absolutely. I believe it 100%! This is the center of the goal, so why aim for anything other than the center of the goal? We might miss, of course, and never hit the goal, but there's no point in doing anything other than aiming for the center of the goal!