Adding 7ths, susses, etc., is a personal thing! I put them in but never write them down, as I never play it the same way twice!!

As it 'appens I usually go from D to D7 between lines to give a feeling of movement (don't want any remarks about constipation, thanx!)...

Added to that, I tend to connect C and Am with a c - b - a bass run, G to Em with g - f# - e, and C to G with c - b - a - g.

Lump that in with wobbling my fingers around on the chords, and it starts to go beyong a simple text explanation!!

Keep an eye open for my next album, as it's going to be on it...