I personally love all string instruments, but violin has a soaring quality to the sound. As a pianist, I am always trying to sound more melodious and less percussive, imitating either a singer(s) or a string instrument. As much as I love the piano, I am limited to a hammer striking a specific pitch and fading. On a violin or viola, however, I can “color” the pitches higher or lower to create certain moods, bring the leading tone closer to the tonic, etc, and the continuous sound of the bow opens a whole dimension of phrasing, dynamics, texture, I could go on. There is so much more freedom of expression if I could but master the concept of relaxing my l.h. As there are so many more possibilities, so there is also more complex technique, training, and musical creativity.