This is just a minor nitpicking preference. It would be really convenient if you could add a ft in the vertical split buffer, so users have the ability to define that ft in an autocommand to close buffer just with q. I don't know if that is something minor to implement or not, so please feel free to disregard this if it doesn't align with your plans.

Whatever the outcome thank you for your time and hard work for this plugin. Really like it and appreciate it.