@newToAudio100 Welcome to the forum! If you like Bliss now, just wait until it goes through burn-in, somewhere around 200 hours... For me, it was not a subtle change. It went from, like this is very good, to like WOW.
I'd like to suggest you try something... Try using your MJ2 as a preamp (high gain, about 3/4 volume), with a pair of dynamic, high gain, high sensitivity tubes, like Gold Lion E88CC, then connect a dynamic driver to Bliss. I didn't notice as much a difference with planars that I've had (including Sus), but man, it makes a pair of HD650's come ALIVE, like I've never heard before. I'm finding that I'm treble sensitive, so I'm sticking with the HD650's, but see how it sounds with your HD800's... Since they are bright, you might need a less bright tube though...
Thanks again to
@Rayon for the inspiration to try a tube preamp with Bliss. You can read more about that adventure in previous pages...
So I've settled (for now) with May KTE>MJ2 with Gold Lion tubes>Bliss KTE>HD650... Have fun exploring with Bliss!