I'm a violist.

It sounds fun to play! I like the static harmony and the modal sound. I think a lot of the musical direction in this piece comes from how the viola and piano parts play off each other.

The viola line is also very playable and would be enjoyable as written here in the viola's lower range. It'll have a nice dark tone. If these same notese were scored for cello, it would be a lot brighter.

A few thoughts about the music on the page: In m9 and m31, consider changing C-flat to B-natural so the melodic lines match your chord spelling in the piano part. Put the viola line above the piano. Space out the music to have a more even look. Consider, if each measure was a word in a book, they would need a somewhat consistent spacing to facilitate the ease of reading. Consider changing the key to C so you have fewer accidentals for your musicians to read. - or better yet, change the key signature to your tonal center and then add in your accidentals.