A wide blade pulls more water with each stroke and is good for working out, speed, and aggressive paddling. White water blades are often designed wider, to pull you quickly around river obstacles or shoot you powerfully over waterfalls. Sea kayak blades are typically narrower, allowing a kayaker to paddle longer distances without tiring. Sea kayakers can increase their cadence but expend less energy because they are pulling less water with each stroke. Try different blade widths.
Most manufacturers have several blade styles to choose from.
Test out really narrow blades like a quill or Greenland style paddle, too. Consider the length of blade as well. Differing blade lengths increase or decrease your working shaft length. Touring paddles are generally asymmetrical. The top and bottom half of the blade are unequal.