rae, sometimes it's not a new piece that is needed, just tweaking how you wear what you have. so take pic 3, try doing a half tuck..as in
http://finalfashion.ca/trend-ender-the-half-tuck/ or
http://joannagoddard.blogspot......-tuck.html
or wear a funky tshirt, or a super drapey tshirt (also will work with the leather trimmed shorts--which i L-O-V-E).
in outfit 2, try wearing a loud sock, or even a white sock...so punk rock. add a white leather bracelet, watch or even a piece of wide twill ribbon from joann fabrics that you sew snaps to, just to make the white sock intentional.
BTW, yoox.com is having a super sale on winter pieces including a lot of helmut lang and helmut lang inspired stuff. for example, in white at all price points.
http://www.yoox.com/us/women/s.....8;season=A
you are so close...you are picking up on the tiny things that make an outfit go from great to WOW.
ps: i think rocker chic is minimalist--see kim gordon of sonic youth. but there is also a strict minimalist esthetic of calvin klein, which i think is too severe for you. but you should fit in with rei kawakobu minimalism