I suggest you are in excellent company here.
This question has been raised a number of times.
It's only money -- sell your beautiful Roadster, and purchase a well-fitted Touring. The Touring is already set up for "good size" and "large size" and is readily fitted with any aftermarket screen you care to order.
The seats -- well -- such a personal preference.
@idk put 130,000 miles on his.
@Boog has in excess of 40K, and recommends a Bead Rider for the long days. Some folks swear by Corbin - you already noted their dear price.
There are a number of threads here where Roadster owners have turned their bikes into Tourings - just takes time and money - hence the suggestion to move to a Touring.
But then, I'm biased -- having selected a Touring from the start.