I'll buck the trend and pick Kirk, because he had the much tougher assignment as captain in a galaxy that was much less settled and explored, and doing so with less technology, less experience and fewer advantages.
Side note: I actually find it impractical to compare two characters from such different eras, anyway. Each served his own time (in the show and in their world) well. It's like comparing Washington and Eisenhower as generals-turned-presidents.
MISSION:TREK's in-depth review of STAR TREK
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