I believe Rasmith has a Concours. He may be a good source for info. Just looking at eBay, there are some larger windshields on there, both new and gently used. Here's one that is at $46 with 4 days remaining.
Look at this on eBay:
There are some new ones available that are wider and taller, up to 26". I would think that would definitely provide some added protection. I don't know too much about the Concours. My brother has been contemplating selling his BMW R1150RTP and buying one. His RTP has an adjustable ride height for his seat, as well as the suspension. Don't know if there is anything similar with the Concours.