Suggest one obsure album we all should hear

dweller2  I was going to suggest Wishbone Ash's Argus for the way-cool and melodic dueling guitars, but you beat me to it, so here goes:  Frank Zappa's first CD was a double, Apostrophe and Overnight Sensation.  He absolutely had his best musicians during this era.  The instrumental title track to the former was written for the ex-Cream bassist Jack Bruce, and he romps.  Jean-Luc Ponty appears on violin, and George Duke asks the question, "Why Does It Hurt When I Pee?" , with references to "The toilet seat", and certain anatomical parts feeling like a "Pair of maracas".  Zappa's guitar work also superb, as are his compositions, and we learn about "The Slime oozing out of your TEEVEE set".

Buddy Guy's Living Proof.  Serious blues from the man whom Eric Clapton called the best guitar player in the world, and about whom Jimi Hendrix said that Heaven would be lying at Buddy Guy's feet while he performed.  In addition to the great electric guitar blues, there are acoustic songs that should be in all stereo demo rooms, in order to test speakers.  

Fleet Foxes self-titled Fleet Foxes

and a desert island fave for me that is obscure to many 
  - Dave Grisman Quintet 80

'Episode' by Avo Demirdjian, electric violin+band

Here is some prog rock from 2016. Start with the 3rd track, when the album really starts to take off. Here's that track at YouTube -- as good as it is here, it truly shines in hi-rez.
Trust me on that. I mastered the album.
https://www.youtube.com/watch?v=dAgP-Su0bJo

Knopfler -  Good On You Son

Mainstream, but awesome. 
Great textures and groove throughout song and actually the whole album. 

https://youtu.be/JIBCHh-fMUE