This piece sounds quite simple, but actually requires quite a bit of musicianship to do well. The interplay of the accompaniment and the solo part does not come through too well in the MIDI sound sample, but in actual performance the accompanist and the soloist can work together to provide a performance lush with emotion.
The piece is written in B major, which in itself can be a challenge. It has a broad range but can be easily managed on a oboe, violin, bassoon, or cello. It would be a much greater challenge on trombone (it is relatively high for a trombone piece) or trumpet or clarinet (in addition to being high, transposition for these instruments puts one in the key of C#).
The accompaniment sounds simple enough, but will also provide a challenge for a developing pianist, both because of the key and because of clef changes in the right hand.
The PDF file contains a score with piano and solo line, an oboe/flute/violin solo part, a clarinet/trumpet solo part, and a bass clef bassoon/cello/trombone solo part.