(1) already exists -- it's called midi (ha, ha). RealTracks derives its "real" sound by recording a bunch of phrases that take care all of those things that Matt mentioned up above for you. As you get closer and closer to one note, you move closer and closer to what midi does with its use of samples.
Exactly!
Consider this: You already have various MIDI samplers that are made by sample recording separate notes of a real instrument and then you are enabled to assign a note value for each note, assembling that into a performance.
But you also know that MIDI quite often cannot sound realistic.
The PGMusic Realtracks get around that problem by incorporating groups of notes - musical phrases - that were recorded in realtime by live very high quality musicians and the software is enabled to select from those phrases and place them intelligently overtop of your entered chord changes.
Trying to frorce Realtracks to play your desired notes, one at a time, is therefore a self-defeating prospect.
On the other hand, there are quite a few MIDI instruments that can sound realistic enough, the Keyboards, Melodic Percussion Instruments, etc. that can, when presented along with a few Realtracks and the Realdrums, sound very real indeed.
And depending upon your selection of the MIDI synth or sampler involved, you can generate some very convincing work. Even using MIDI guitars in the case of some synths.
--Mac