Mi Dolor by Juan D’Arienzo. Pay special attention to the unique interpretation of the bandoneon solos.
Lazzarella by Domenico Modugno. Not a traditional milonga but definitely something fun.
Pata Ancha by Osvaldo Pugliese.
Te aconsejo que me olvides by Aníbal Troilo y Francisco Fiorentino. Beautiful, rhythmic, and flowing. A great example of dynamics to strong music.