Thank you for taking the time to listen and comment, Andrew!
I agree, it might feel kind of bland, but at the same time it seemed to me that adding too much texture to such a simple arpeggio when everything else is happening outside the piano and harp part felt overwhelming. I couldn't come up with anything different but for the harp to stress the last four notes of the arpeggio. The poor mixing definitely is the responsible for the lack of clarity in that sudden modulation.
Thanks again!