In a glass measuring cup, combine the warm water, yeast and 1 teaspoon sugar; let stand until foamy, about 5 minutes.
In a large bowl, combine the flour, remaining 2 tablespoons sugar and the salt. In a medium bowl, melt the butter in the microwave. Stir in the milk and microwave for 30 seconds more. Stir the milk mixture and the yeast mixture into the dry ingredients until almost smooth. Cover with plastic wrap and let stand at room temperature until doubled in size, about 45 minutes.
Beat the eggs, then mix into the batter. In a small saucepan, warm the maple syrup over low heat. Add the raspberries and mash with a fork.
Heat a griddle or large, heavy skillet over medium heat. Spoon 1/4 cupfuls of batter onto the griddle. Sprinkle a few blueberries onto each pancake and cook until bubbles appear on the surface, 1 to 1 1/2 minutes. Flip and cook until springy to the touch, about 30 seconds more. Repeat with the remaining batter and blueberries. Serve with the raspberry syrup.