I tend to keep a chisel tip just about the same size as the solder pads in my iron 99% of the time. A good solder station will dump plenty of energy into the tip for some larger soldering jobs, and on even larger jobs a little gob of solder on the tip will effectively make heat transfer even better. I do use a large tip for truly large jobs, like soldering to the back of a pot, but that's pretty rare.
It helps to feed the solder somewhat slowly, or in short jabs. That keeps the joint supplied with a constant supply of flux. That's how you get those beautiful, shiny, flowed out joints on solder tabs and things like that. That's also why it's pretty important to use a separate flux if you're going to drag solder something....all the flux is gone from the solder on the tip in the first couple of seconds.