Speaking of Mile Davis, I think that 'Kind of Blue' is a bit over rated, and over played. John Coletrane from that same era on the other hand is quite good.
In my opinion, Miles Davis was at his most interesting period when in his electric phase, starting with 'Bitches Brew'. I fairly fond of ' On The Corner', 'Live Evil', and 'Dark Magus'.
As far as really outlandish Jazz, though, you'll probably want to stay away from Sun Ra as well as Peter Brotzmann, Jaap Blonk, etc...
Well there you go. Another opinion, just like that.
Personally, I like all the Bitches Brew material, funk, spacy all of it. Coltrane made some of Davis' music special, too. Coltrane rules! Never a question, there. I also play a lot of Coltrane (and recommend it highly!), including his wife's and kid's music. Alice Coltrane died this year - Ravi Coltrane still records. I think I have all the Coltrane, but a long way to go on collecting Miles Davis.
Funny you mentioned Sun Ra. I played this one earlier today:
