Thank you for such a detailed review, this is the most useful feedback I've got so far.

You are right about the icon and the font size, I will fix both. Japanese and Chinese text does need to be larger than Latin, that was my oversight. I will also check the contrast on the coloured backgrounds.

The equalizer under the spectrum with dB values is a great idea, I am noting it down for a future update.

Thanks again for taking the time to write all this.