AFM kind of nailed it. The KLR is out of production but the most current model goes back to 2008, so plenty of bikes and support around.
I've been around DR650's for 9 years now and built two. It's been the same bike since '96 and is highly supported in the aftermarket. You can make one to suit your mission. At your weight, it's sprung about right, maybe a little soft. Capable for what you stated. To gain confidence on it, the bike can be lowered 1.5 inches by switching a few parts around. Put it back to stock later. This is what we did with my son's.
Can't comment much on the others, but if you like tall bikes, check the Honda XR650L, too. More dirt oriented and the same bike since '93, so plenty around.
If you ever want to "go over" a DR, happy to talk ya through mine. Just PM me.