During my less than successful attempts at intentionally catching chub last winter I wanted a rig that would allow me to vary the length of the hooklink and still take the force of a fair cast. My first rig failed the casting test as the stop slipped. The rig I eventually settled on is shown below. As well as having a variable hooklink it can also be used as fixed or running by sliding the Grippa Stop up or down the line.
The main line is 6lb Daiwa Sensor as it's tough and cheap. The leger link is lighter than the mainline, and preferably lighter than the hooklink too, the hooklink being Reflo Power Line in 0.15 for flake, paste and worm, lighter for maggots when I feel the need. Hook pattern and size being chosen to match the bait.
The snap link on the end of the leger link allows the cage feeder to be swapped to a maggot feeder or bomb as required. I carry a few of these links, with a loop on the other end, to make retackling easier in the dark after a feeder is lost to a snag.
All pretty self explanatory I think.