I have liked this movie over the years. I suppose not everyone gets it or gets into it. TWBB is one which you can watch and think about and interpret different things about it.
I've watched TWBB 3 or 4 times over the years. Once in 2007/2008 when I was 19 or 20, back then I probably thought of Daniel as more of a silly over-the-top character, but in recent years I have found interesting some other things about it. The depiction of the early 20th century oil industry, greed, entrepreneurship, how Daniel seems tough and sociopathic but deep down really wanted a family/be part of a family, and he ends up very wealthy but alone, How child Mary Sunday is the only person he seems to show some real care for early on, when she is apparently being b**ten by her father (Google thinks this review is spam). Was Daniel also abused similarly as a child, hence his personality and beliefs now? How a couple of scenes, in the desert at the beginning, and the bowling pin at the end, have some similarity/parallel to 2001 a space odyssey.
The only thing is, I agree the ending is a bit clumsy/unsatisfying, perhaps a couple more scenes of Mary Sunday and HW and Daniel getting arrested.