I've had great success with the following:
Nickel:
Ken Smith Taper Core Burners
DiAddario XL's
Steel:
Dean Markley SR-2000 (The best steel string on planet IMHO. -"Now watch them get discontinued"

)
All in Light to Medium Light Gauges.
For what it's worth, my current main bass the Smith BT6G is at it's best with the Smith Taper Core Burners.