I think you're not tonguing clearly, but rather "chewing" each tongued note. The embouchure and air stream should remain constant while the tongue comes in to interrupt the note. This is why the pitch and tone often wobble right at the beginning of notes.
I also think you could stand to put some more air through the horn - not louder, just more of a reserve. That would also help with the way the long notes kind of die out. Keep the intensity of each note clear through to the end, unless you intend to diminish it, in which case do THAT very explicitly.
I think that imagining a constant column of air flowing from somewhere around the navel up through your abdomen and chest and out through the bell of the horn, and practicing that way, will also help smooth out some of the roughness and reediness I hear.
Really, you can do pretty much anything you want on a 6M; here's Marshall Royal of the "singing wailing" school of tone on a 6M:
View: https://www.youtube.com/watch?v=xkIZ37pM6ms
And here's Lee Konitz of the "dry, clear" school of tone on a 6M:
View: https://www.youtube.com/watch?v=IG6h-eqSkJQ
Me, I tend more toward the Arthur Blythe and Sonny Criss schools of tone (neither man played a 6M but I have no issue getting that kind of sound).