My process for film scoring emulates the traditional live scoring process:
1 - The composition starts in my head, then written with pencil and paper, usually 8-stave sketch for orchestra.
2 - The next step, if the process were live, would be to send it to the orchestrator to write out a line for every instrument, based on the sketch. Since I'm doing this virtual, I skip this step and record each instrument from the sketch, which can be tricky for something like stacked parallel WW runs, because I try...
3 - ...to input each instrument in real time (slower tempo if the piece's tempo is faster than my playing ability) as if it were a live instrument. Rather than drawing in CC's, or stepping in notes, I try to perform each instrument and record myself as if I were recording a live instrumentalist. I use a WX5 for winds and brass (and solo strings), pedals with a keyboard, drum pads, and I'm even trying to learn to use Leap Motion/Geco. Anything that allows me to be as musical as possible. And, like I would if I were engineering a session with a live player, I keep recording until the take is right, and will splice different takes if I'm unable to get a good single take. I favor sample libraries that allow maximum playability, so that I don't rely on the samples to provide a musical performance - I rely on my own musicianship.
4 - My mixing process also emulates the live process. When recording live, there will be a room sound when recording an orchestra. So my first step is to have my instruments placed in a virtual room, if the room isn't baked into the sample. Right now, I use MIR/Teldex. Once I'm that far, I'm up to the step where a recording engineer has a multi-track recording of an orchestra in a room. So from that point, the mixing process is very similar to what I would do if I were mixing a live recording. I might use a reverb with a nice tail, 24ms predelay, to enhance the existing (artificial or baked in) room, light compression, EQ...whatever the piece needs.
That's my process for realism/musicality. Best with yours!