Hi Dave! I hope your journey is progressing along nicely. The only thing that I can add is make sure you are always in tune and to always play a guitar that inspires you to play and pick it up often. Take lots of little breaks. And keep at it. You don't have to MASTER chord changes before you move on but they should be sounding like notes before you move on to the next lesson. Strum a chord, pick the individual notes and make sure they are ringing out clearly, then strum again. If they aren't rigning out clearly make little adjustments with your fretting hand fingers and keep picking the buzzing note till it rings true. Then give it a final strum. This method may not require a metronome but once you start improving your chord changes a metronome can be very benficial as well. Keep us posted on your progress and best of success!

Jibran