I always thought a sunroof was so great...now that my car has a sunroof/moonroof I realize why some people don't buy them. They are nice to have, but I mostly like to use it in "tilt mode" when it's raining so I can have the windows shut and still not have the whole car fog up or get too humid. It actually gets used maybe once every two weeks or even once a month sometimes...seems like kinda a useless feature...t-tops seem like they would be more open and actually serve a better purpose.
As for riding a motorcycle cross country, definitely make sure your skills are up to par. You will be traveling into places that have different intersection layouts and different road conditions. Make sure your bike is also up to the task too. You should have a tire patch kit at the least...if possible I'd try to get people to travel with you that have the same tires front and rear...and then one of the riders carries an extra front and another carries an extra rear tire - obviously without the rim lol. You could always just carry a patch kit and a can of fix-a-flat, but remember that depending on how traveled the roads and areas that you're visiting; there may not be any tires that fit your bike's rims...and that could be very bad.
Make sure your bike is also comfortable enough for long hours...
You might want to make a stop to deal's gap, it's on the border of north carolina and tennesse rt 112 or 118 or something. That's where I want to visit this summer...318 turns in 11 miles, most of them switchbacks (180 degree corners...aka hairpins)
