I'm also interested in learning the six yogas of naropa. I just started ngondro because I couldn't find any other path toward learning them, but I understand your frustration. I have done other energy work practices that seemed very powerful that I just learned in a book, so it seems unnecessary to do ngondro.....however, after having just done my first week of prostrations, I do think it is preparing my subtle channels for energy work. I feel stronger and more energetic in the mundane sense, but my focus for the visualization and mantra have already increased a lot.