Sitka Spruce is the most well-rounded tone wood and is used on more guitar tops than any other wood. This is due to the tonal qualities and sonic projection of spruce. It has a nice even tone and does not accentuate any frequency above another in an overpowering way. Spruce also has a strong attack and does not get muddy at high volumes. This makes it a very versatile wood and makes those players with soft touches sound great and people playing with other instruments cut through the mix.
The dreadnought body shape has been the most popular shape for decades now for a number of reasons. First, it has a nice balance between low, mid and high frequencies. Where some body shapes scoop the mid range, a dreadnought will bring the mid range up. This is important when playing with a group of instruments. The mid range of a guitar will stand out. Because of the tonal balance of a dreadnought, the sound does not get muddy and will be very articulate even when a player is a more aggressive picker.