If you have a MIDI file that needs some extra layers of notes or better instruments, I can help by using my extensive library of professional VSTis and samples.
All my music compositions are done via mmidi format for several years now so I have great experience in working with this kind of format: http://www.youtube.com/watch?v=jtX2a7y3QKI
Starting from one gig per 3 instrument replacements or one gig per one layer of new notes, I can deliver you a drastically improved MIDI or WAV.
Make sure you check out my extras bellow to see the other cool options.
Feel free to contact me for more details.