I voted mono, but I use braid too.
here's a breakdown of the lines on my most used rods
6'6" Ultralight - 4lb trilene XL or XT
7' Light - 6lb trilene XL
7' light walleye rod - 6lb fireline
7' medium - 10lb fireline
9' steelhead and carp rods - 8lb maxima
catfish rods
50lb power pro or 20lb trilene big game
bass rods
jig'n'pig - 50lb power pro
froggin rod - 65lb power pro
texas rig rod - 15lb McCoy Mean Green, or 14lb trilene XL
Spinnerbait rod - 17lb Trilene XT
dropshot rod - 15lb trilene big game or 50lb power pro
hardbait rod - 12lb trilene xl