UPDATE: In Blood Money, the first episode of the final run, we see Walt put down a towel to throw up.
Just like Gus Fring did a few seasons back, when he visited the bathroom after poisoning Don Eladio's crew.
So that backs up the "Walt takes on traits of those he kills theory". And with that in mind, the following image - also from Blood Money - is particularly chilling...
WALT WEARING THE SAME COAT AS JESSE.
Getting excited for the final episodes? If so, these words from Breaking Bad cinematographer Michael Slovis are worth a look.