I generally use a separate track for each articulation. I could never achieve desired results by key switching, maybe because I find it necessary to layer different articulations together for realism. (EWQL SO, Hollywood Strings).
I will also have 1 instance of play per instrument.
Instance 1 - Violins 1 and 2 with all their articulations
Instance 2 - Violas and Cellos - with all their articulations
Instance 3 Bass - sometimes Bass + Cello if I had to share V2 with Violas
Brass is set up similar.