A few of the details that really help crisp-up the overall look of the house include:
Painting the previously painted(white) garage door handles black.
Repainting the mailbox, adding a new porch light fixture...the previous one was too tall for the space and it was nearly impossible to remove the top to replace the light bulb.
I've had this little topiary for years and the base was painted white, I really think it helps pull the look together to repaint it black.
We repainted the columns and porch post and light.