If you have good piano skills, why not try your hand at some piano only arrangements first? Or maybe a sonata? That way, it’s easier to focus on the essentials of arrangement and composition without getting all distracted by technical stuff such as plugins, MIDI, controller data, etc. If you can make something sound good and complete on piano, it should be easier to translate it into something different and more fully fleshed out than doing it the other way around. After all, being limited to 10 notes max does kinda force you to get the essentials of the piece down.