Hi, here are my initial design for you to review.
Actually I was going to create a character for you since based on the brief you wanted a character. But I'm afraid using a character / mascot for your logo will makes your logo looks bit playful / fun, and bit loud while according to the Stylistic Sliders you wanted your logo looks subtle, and serious. Please feel free to discuss so I can help you to create the best logo for you.
You can also look to my portfolio in case if there are some of my work that you like and can be used as a reference for your logo. Please take a look at here :
https://logotournament.com/logodesigners/musicalryoI loves drawing character, I just wanted to make sure that I'm on the right direction before I go any further.
I'm looking forward for your feedback.
Thanks!
Ryo