I don't think power will be an issue but it's way hard to get the convenience factors of a real tourer on the america. I wouldn't say you'd miss much on a "3 to 6 hour ride" but some of the locales you mention sound like 1500 mile, multi-day trips.
The style and feel of the America are what keep me in the saddle but my advice would be to try out some purpose-built tourers along with the america and see what floats your boat.
