May I suggest a 5 hour set of tutorials on MIDI orchestration?
How best to layer strings
How best to produce great violins by using different articulations
Orchestration mechanics/settings
Effects
What goes together well
How instruments are usually used (eg octaves, call/answer etc etc)
How to use brass correctly
The list is endless
I have the fanstastic book on MIDI Orchestration by Paul Gilreath but I would LOVE to see his techniques and knowledge shown in Logic or whatever using say VSL and/or EWQL etc
There are so many complex elements to midi orchestration it could be a mammoth set of tutorials but I think it would sell well for you. I for one would pay $100+ for the download version without hesitation
The more I think about it the more I would love to see something like this covering all aspects.
Thanks