Hmm, my suggestion is for 1 on 1, is get an adventure, then create a character that is 5-8 level better than the adventure.
So a 2nd level adventure, you take a 7th level character in, though a 5th level might do, and as Conanistic or Elric, has the adventurer have a friendly NPC friend with them. Of course some of Howards work had the damsel in distress, but not every time. Nestor in Halls of the Dead, etc was a fighter; so have a lower level NPC with them, with the example above; the NPC could be 3rd to 5th level depends on how you agree with the suggestion.
I am myself a little short of players and in time have been attempting a solo type play, so creating charts etc, but it for Conan D20, so it would be of no great help at it refers to different creatures, etc and it just by no-way near finished.
I got a lot to do, I working at Larsha, City of the Dead. I post in next few days in Maps forum below, got a lot of maps, so will add some Encounter charts so you might try a random/solo adventure.