Focus on imprinting the patterns of the chords in YOUR HEAD. Once you can visualize the chord patterns, then you need to work on having [u]all [/u]your fingers land on the fretboard [u]at once.[/u] If you place your fingers one at a time, your are probably all ready out of time with the beat of the song.

SO...First= visualize the chord patterns. Second= learn how to place all your finger in position with one shift movement. Lastly, work on your picking pattern. Chords should not be shackled to any specific picking pattern. So work on steps one and two until you are no longer getting derailed by this "base note must be start the chord" problem.

Maybe just work on strumming the first beat of each measure until you can make all the chord changes in time with the rythym of the song, without missing any beats. Only then, gradually, work on specific picking patterns.