That album is more inaccessible to me than a lot of avant garde stuff, it's hard to explain, it's just too ugly for me for the most part.
I consider it a great album though because of the ground it broke for the time and there are indeed some awesome tracks like Moonlight on Vermont, Hair Pie Bake 2, Ella Guru and Big Joan Sets Up. But there's also stuff like Dachau Blues, Pena and Hobo Chang Ba which is just astonishingly awful.
It's a good album for what it is but not the flawless masterpiece people make it out to be.