Rautavaara,
You've got some very good ideas. I really like what you're doing with your rhythm and there's some good melodic material there. A suggestion, at bar 22, you have all three wids in unison. This sort of doubling may work in an orchestral tutti passage, but generally in this sort of chamber music environment, lengthy unison passages don't work too well. If you want to use all three tone colours, I would recommend splitting off the three instruments into a chord of some sort on the higher notes as well as the Eb at the end of the passage. I think it will give a better effect (in my opinion anyway. It's your piece, and you can do what you want). Also in the passage at bar 38, you have scored both violins, the cello, and the viola very similar registers, while the 1st violin and cello are carrying separate melodies and the other two instruments are playing harmoies. It will be difficult to distinguish the melody without a significant dynamic contrast between harmony and melody lines, seeing as you have four separate lines, all with similar tone colours, all in similar registers. I would recommend moving the first violin up and octave and possibly even giving its line to the flute. The cello in its high register is a great effect, but I'm not sure it would work here. I'm pretty sure you can put it up another octave and still have it in the cello's range (don't quote me on it though) although you would probably have to use harmonics, which tend to sound thin. It might work though. Alternatively you could give the cello line to the clarinet.
Anyways, it's sounding very good, and very refreshing. Keep working on it.
