What I usually do when I write music is rapidly strumming barre chords in 4/4 timing. I love 16th notes. I don't use barre chords all the time however, some times I use sevenths. I lot of punk bands have simple chords its just that they are played pretty fast and us punk rockers aren't the best of musicians so we tend the mess up all the time even while recording.
I like to use the note that's half an octave (at least I think this is what I mean) away from the Key note. For an example I love to go F to Bb and G to C.
I'm only a beginner at vocals so I'm not the best but if you want to hear some of my music, go to reverbnation.com/axetheace
remember as I said, I'm a beginner vocalist so no trolling lol.
Axe the Ace Tyler Robert Baugher