Just a Song Sunday: Chord Progressions

Lately, I've been playing around with a chord progression. I haven't turned it into anything other than the progression yet, and I might never add words, but I am enjoying what happens musically, and I use it to center myself. Here is the progression (I use the key of D most often). All of the chord symbols last for the number of indicated beats: I///IV///I///IV///vi///V7///vi///V7///Repeat For some reason, this progression is something that helps me focus. I love the juxtaposition of the vi chord in with the others. I've been playing this for a long time now - for at least 6 months - without being able to do more with it. I've decided that the progression doesn't need a melody at this point. One day it may include a melody and lyrics. Maybe not. I don't always attend that closely to the harmonic element of music. It is something that I often take for granted, but there are some progressions that stick with me. I thrill to most of the harmony written...