Welcome from Virginia!
My last bike was a '94 K1100LT that I enjoyed while it wasn't busy being a lemon (rear seal leaked 3 times in 2 years, killing the dry clutch plate; Two of those times were due to dealer repair suckage).
I can't give you any stats on the tires yet, only have 750 miles on mine so far (bought it 10 days ago), but I'm sure other folks with lots of miles will chime in.
Even though the R3T is heavier, I know to me, it sure feels lighter than my K1100LT; The K1100LT always felt top-heavy.
In terms of annoyances? Some folks complain about the heat these things generate and some folks riding on the back aren't keen on the foot placement for them. For me, if it's a very hot day, well, yea, the heat it's throwing out does make it worse but it was my choice to go out on a super hot day already so that's on me hehe.
I think some design choices on the R3T are a little puzzling.....The seat is bolted on but the side panels are simply pushed on to a grommet.....I've had one of those fly off at highway speed (my first ride in fact). On the tour, the seat should be removable with a lock set-up and the side-panels should be bolted on (which is how the R3R is set up).
They should have included a windshield lock, from the factory, and the gas-cap on the R3T should have been lockable just like the R3R from the factory as well.
As full disclosure, if you look up "eastern beaver tail" (headlight bypass) and "negative battery cable", you'll find some posts here about needing to replace/upgrade those at some point for some folks.