That's the reason I moved to the HTC, I wanted the bigger screen and I was able to get a much better deal on the M8.
Anyway, I appear to have found my solution. I had a chat with a colleague yesterday who's been using Android for a number of years ankd she showed me how to upload all my music from iTunes to Google so I can then download what I want on my phone wherever I am using Google's Play Music app which is way better than HTC's own music app. I can then use Google Drive for photos. Never need to plug the phone into the Mac again!