Hi there :) My name is Stefan. I'm a professional audio engineer and composer, working in my own business (recording studio) with a experienced team of two co-workers.
We have done quite a few similar jobs before.
For the music fade out part I like to use side-chain compression, means that your voice (the send channel) will decrease the volume level of the music, so the music will fade out and be in the background, like in the radio.
Overall quality could probably be improved (mastering)
If you have any questions, don't hesitate to contact me, I'm always happy to assist :)
Kind regards,
Stefan