The way I learned tunes was to play whole chords all the time, make the thumb work properly, and just scratch around with the index finger until I was in a position to start working on the fancy bits and use the other fingers. If you play partial chords you have to keep the volume down or the "inner voice" does not sound good. If you've been flatpicking all your life you might find it easier to use the flatpick for the thumb parts and use the second and third fingers to pick with. The first book of Leaonard Cohen's songs had good tab and encouraged learning fairly simple but methodic picking, if you can stand playing Doom From a Room in standard tuning. The glucosamine tablets worked for me, too!