Great way to work with faces/portraits: rotate them, x's over mouth, eyes, etc. Also--visually cutting off the top of the head and having something coming out (can be a reference to something creative, or just an aesthetic element).
Cristiana Couceiro is a Portuguese Illustrator living in Lisbon. Her work is focused on making collages using newspaper, tiles, vintage photos and pieces of paper in a very clean way and strongly reflecting a retro look.
Neil Kellerhouse does some great movie poster and packaging work. Texturally provocative and edgy but also very clean and conceptual. He also uses typography in a very conceptual way. Poster for "The Eclipse.