When I started out, I hated writing my dreams as well (still do really). One big advantage of writing outside of the obvious is that it takes no trouble to pick up your journal and ponder the previous night's dreams and your corresponding mistakes (before bed is a great time for this). With audio it might just be too easy to file it away and forget about it. Also, if you tend to use multiple techniques during the night that interfere with immediate recalling time or spend a lot of time lucid dreaming, the process of detailed writing is the best remedy to bring the earlier material back.