Personally I've given up on creating midi parts. There are some good midi samples around for drums, piano and bass. Nothing else sounds anywhere near realistic enough and I have some Kontakt instruments.

Realtracks are the future for sampled music and that is why I'm such a huge fan of BIAB. The best alternative is to do a session with a real musician. You'd buy a lot of bespoke sessions for the cost of a decent midi library.