I use East West Quantum Leap (composer's collection; I chose Symphonic Orchestra Platinum, Pianos, Goliath and Storm Drums, amongst others). These samples are premium and typically work best in 64-bit environments. That said, Ableton in my opinion is still the best for creative workflow.
I'll add instruments to each track as I need them and play a part. Using scenes to launch is important here to keep the appropriate parts together. Then, as with other styles of electronic music, Duplicate and modify with variations into each subsequent scene. The clip view is extremely useful for trying different parts until lots of options exist. Then the arranger mode is used to put things in the right order. With classical you end up using tempo changes more frequently. For non-4/4 beat electronic music flow, I use the clip view for experimentation and the arranger view to build the song like in a traditional DAW.
Ableton easily allows tempo and time signature change automation too, so composing in a traditionally linear time-based manner is your thing, just work from the arrangement view. What's lacking is sheet music conversion, though Cubase is good for that if you need sheet music from your piece.
Don't know how much this is helpful, just my take on it