The formula says you have to add a total multiplier of x1.45 (after you have added profile cost of speed, shields, turrets etc and weapons together) to have 6+ all round but this also includes the abilities of having SM crew (+2 boarding, +1 hit n run, +1Ld), so if you technically want 6+ on a "normal" crew you have to adjust accordingly to what seems reasonable ~x1.2.