I must be feeling better...
...because I'm thinking about chord progresions. Sometimes it really is tempting to just write songs that use only I, IV, V, and vi chords. Half of the songs on the radio are that way. Throw them all in C, G, F, or D...and you've got praise and worship in a hand basket. It's amazing what can be done so differently with so few structural changes. I mean, really, take three-four harmonies, and, through different lyrics, melodies, and timbre and textural changes you can make a million different songs. So why do songs that don't modualate, use secondary dominants, or even just more freaking chords in the home key bug me so much?