The violinist who really got me inspired to dive into tango was Fernando Suarez Paz on the album Tango Zero Hour with Astor Piazzolla. I had never heard anyone play like that before, such langorous glissandos and notes filled with longing. He really has a sound all of his own. In many ways he defined the sound of tango violin for Piazzolla's music.
Another violinist who is considered to be one of the greatest ever is Enrique Mario Francini, one of the few to play with a dazzling virtuosity that is always musical. He was filled with ideas on how to define his playing in his solos and regularly soars between the depths and heights of his violin using trills, double stops, octave leaps, you can really hear how much fun he was having! Recommended album is with Quinteto Real and Horacio Salgan.