Pretty interesting. The melody sounds quite light and airy. Uhmm, few suggestions. You don't have to mark spiccato, generally that is the articulation used, when notated as in the score. I can't think of the term right now, but at measure 59, you may want to have the violas "splitting" the parts. Also , at the key change to c major, those harmonics are very difficult to perform, so you might consider adjusting it. Overall, quite good music and orchestration.