I would go for the DR, or even if you're looking at a new bike the new husky 650's aren't too pricey but look like they'd check most of your boxes.
But after all, if you're buying a cheaper bike to spend money upgrading it to make it better you might as well just spend that money on a more suitable bike from the start. Once you start adding up all the farkles to make a KLR able to tackle single-track (without having the patience of mother teresa) you might as well buy a beemer or ktm.
Of course YMMV
There's only one rule that I know of, babies - God damn it, you've got to be kind.