If you are inspired to make something great, find a song that you love and one that you can hum backwards, and make a digital sound of that song,
You will learn how different songs and tracks fit together, how you can alter sounds to make a sound you want that will sound just right, or even familiarize yourself with your player to a much deeper level
Beyond that is listen to people on how they do their transitions and syncing with different tracks!
Now, as for your song.... *listens*
Add more tracks to your baseline instead of a simple track that will play all the way through, you would not hold your breath for more then 20 seconds at a time, a background beat sound should not play for 20 seconds without alteration or being changed out for the same beat but with a different sound.
Liked the voice and the piano you went on, work on your background noises more like you're:
Bass line, and tempo line track... They are where you lack the most in realistically
(i know that as you change those the others will follow suit and you will strike sound wave gold
MMM! You figured out how doing a backwards track to make a transition!
keep up the good work :3