Are you married to the idea of a DL1000? The DL650 will do the stuff you're asking for, and will do it cheaper. MPG for the 650 is going to be in the 50's, which will be better than the DL1000, plus the 650 will run on 87 octane fuel. The 650 will cruise along just fine at 75-80 mph, though your mileage is likely to drop into the mid to high 40's (which will still be better than the DL1000). The 650 is lighter than the 1000, which may be a factor for you since you're coming off a KZ400.
I put a lot of two-up miles on my 650 before I traded it; it's a very nice two-up touring platform. My passenger and I took multi-state trips on my 650, with a load of gear, with no issues.
"No matter where you go, there you are."