This depends, I do a lot of light tackle jigging with 1/16oz and 1/8oz jig n pigs with big hooks, I throw these on a Kistler 6-6 M Helium spinning rod He66MS with a Stradic 2500 and 6lb Yo Zuri Hybrid
For casting I tend to go light also and I normally use 15lb Vanish Fluoro on a Shimano Scorpion 1001 and 7ft M Kistler Helium LTA He70MC rod. This set up can handle 1/8oz and 3/16oz thru 1/2oz jigs comfortably.