Two features, likely already done:
1) Path to store music should be browseable! I couldn't find my SD card, every time my memory was full it turned out its because I didn't have time to search the internet for the path. Alternatively, just a big button for "external SD card" (since my Galaxy S3 has an internal, confusing SD card as main memory)
2) I know this isn't your fault, but a work around to keep the volume at its setting from last time would rock. Android (4.x) takes volume to ~60% whenever you start an audio program, then you have to go back and turn it up manually. EACH TIME. Uhg.