If you're interest really is in the sporty end of touring, I can recommend the ST1300, having ridden one for three seasons. It's not quite as light or quick as the FJR1300, but it is a real gentleman, and handles very well. It's a baby Gold Wing, but with more snap. As for the passenger, it's a mixed bag, and I feel that having had small passengers and more "normal" sized passengers, I'd have to say the smaller passengers fit the ST well, but larger sized ones are less comfortable. The ST, though, is a wonderfully smooth, comfortable, long distance mile burner, deluxe. For me, it was always a delight to ride for any distance.
That being said, if 2-up touring is your main interest, the GL1800 is the logical choice. Nothing can compare with a Wing for touring comfort, power, handling and overall ease of maintenance. It's a big sportbike with luggage. I, too, have tried the LT and was disappointed for all the reasons mentioned above. I have returned to the Wing because my wife has desired to ride as a passenger from time to time, again, when her back and arthritis leave her feeling that she's not up to riding herself, and because we wanted to pull a camper trailer, and I felt that the ST, while it certainly has the power, just isn't the kind of bike to tow a trailer.
Rent an FJR, an ST, the LT, and the Wing, compare, and decide which one speaks to you the most and go for that.