1) You will love the HD Deflectors and Sancho's Wings. Install those 1st before installing the shield. You might be happy with just those mods. But in the end, the Madstad is a great choice, they simply work.
2) Your description of the wrist and finger pain perplexes me. These are not typical symptoms of bar discomfort. Most of us that have had issues, had the pinch between the shoulder blades, or sore shoulders. Having pain in your wrists/hands would be typically due to grip. If you have too tight a grip, even short of being a death-grip, you will get these kinds of pain, plus forearm pump as well. I doubt, based on your description that a bar change will help you.
Another thing to consider is how you lift your bike off the sidestand. I know it sounds odd, but bear with me...
None of my previous bikes weighed nearly as much as the RG, so the first week or so, I had soreness in certain muscles that weren't used to being used like they are on the RGC. My Hammer S weighed in at just under 700lbs and my Ducati Diavel Carbon weighed 425lbs. I typically would get on the seat, and bring the bike up with my arms/shoulders and not so much with my legs. I realized after the first week that my shoulders hurt quite a bit, and that was due to how I was lifting the bike. I went back to a traditional "lift with leg" approach, and the stress in my shoulders went away. Perhaps this might be one part of your issue as well. All a part of getting accustomed to the ergos of a new bike.
Let us know how the new bars work out. Maybe changing your grips might help too.
2012 Road Glide Custom Black Denim