Have you ever found a graphic or photo that emulate a style that you became giddy about?
In the last year, I found a graphic showing this neon sign style (I think they called it "colored chalk style") that I instantly knew I had to cookie-fy. 

This method is super easy and fast since you don't have to actually outline and flood the entire cookie and then add additional layers of icing.

Start with chocolate cut-out dough, and cut and bake any shape that will be recognizable by just adding a few outlines/silhouette. 
In the set shown, the theme was coffee related, so I picked the shapes accordingly.

Once the cookies are baked and cooled, combine vodka (or a clear extract, ex. almond) and Americolor Super Black gel to make a "paint" to cover the tops of each cookie. Brush the opaque mixture over each cookie and allow it to dry for a few hours before adding the glaze.

Use bright "electric" colors of glaze to add the outlines and single detail lines to each cookie.