Welcome to the forum. For me the bike is just too much fun with the stock sprocket so I don't know if I will change it. I'm not one for interstates anyway.
IMO there are better bikes for interstate travel than the Versys. You really need to decide what you want to do and where you want to go. The Versys is an all arounder. More like the UJM of the 1970s Not great at the extremes, but does everything OK.
For interstate travel I would opt for a heavy bike that won't get blown around and provides excellent wind protection. Not sure where your budget is but I am assuming it is around $5k. I would be looking at an '07 Kawasaki Concours, a 1600cc Vulcan LT, or something along those lines for the type of riding you described.
Of course comfort is a subjective thing and you don't state why your current bike sucks on the interstate. If it is because of wind then you will not like the Versys without modifications.