I have to disagree, the risk of bad & imperfect recruits is part of the game.
I would like to see Traits classified as Hidden, Visible or Trial
Hidden are always a surprise (e.g. Dastard, Bleeder, Blood Thirsty, survivor)
Visible are obvious to the naked eye, so should be shown on the recruit screen (e.g. Tiny, Fat, Strong)
Trial stats would be revealed if you pay some gold (say 5 or 10% of hire cost) to put that recruit through his paces (e.g. Iron Lungs, Sure Footed, Dexterous, Asthmatic, Clumsy).
Under this mechanic most traits would still be hidden. But it would really help the Ironman player in a sensible way.