Your main problem with auxiliary outs is that, unless the effects section is doubled or tripled in its entirety, the aux outs have to be bone dry. The main reverb and chorus sends all go to the same section, so there's no way to separate the reverb return to the drums from the reverb return to the piano, for instance.

However, I think it would be wonderful if an aux out (and the internal speakers) carried a separate mix of the entire output. Even something as simple as an increase in the balance of the Keyboard Parts to the Style/SMF/MP3 Parts would help us hear ourselves better without swamping the backing, which is something I tend to hear in 90% of all user demos. If we could up the 'me' in the mix without it being reflected in the main outs, that would be really useful!