Decided to go mostly with street-levelers, and with no characters that are too powerful to be threatened by any of the natives. Certainly no "solo the setting" peeps for me. Also, it would be nice to have people who can actually teach me some of their skills in the process of adventuring, so I wouldn't have to be completely redundant to the team effort. So I'm picking:
Walker, Texas Ranger
Finn and Jake (Adventure Time)
...and Cameron (Sarah Connor Chronicles), programmed to protect me. Should have decent survival odds (Cameron probably can't be hurt one on one by anything short of a dragon, and Jake, while not an expert combatant, is an enormous practical asset) while still having a challenging time. Not to mention fun.