My channel hit 6M+ views… but now I don’t know what to do

I currently run a YouTube channel with 5.84k subscribers and 6.1M+ total views. Most of my growth came from K-pop piano “guess the song” shorts/reels, especially around groups like Stray Kids and BLACKPINK. Over time, the channel became very strongly tied to that audience and niche.

The issue is that now I want to branch out into broader music content like western pop songs, vocal covers, guitar, songwriting-related content, more artist-focused stuff instead of only K-pop piano quizzes. But whenever I post non-K-pop content, even if they are in the same format (like guess the pop song), my existing audience usually skips them quickly, so the videos die early and never seem to reach the actual audience that would care about them.

What makes this confusing is that all my current momentum, subscribers, and reach came from one specific niche, so I’m worried that trying to expand too aggressively might hurt the channel overall. At the same time, I also don’t want to stay permanently locked into only one type of content when my long-term goal is to grow more as a musician/artist and not just a K-pop quiz page.

I really need help from some experienced people who can tell me how to manage this situation.