I'm happy I was able to help with my feedback. I'd be happy to play the update once its posted.
My design process for creating boss fights is finding ways to test the player's familiarity with the game's mechanics in fun/creative ways. For your game, I would think about what gameplay mechanics you want to test the player on and work from there. Personally, I think there's a lot of potential in incorporating fake platforms into the boss fight (especially since you're adding more feedback to them).
Best of luck to you in your game dev endeavors!