Need help in imitating orchestral sounds/techniques

[Likonan]

I've always been curious as to how I could replicate a number of orchestral techniques and instruments without losing some of its "life", as I call it. But being such a difficult genre to master (for me at least), I was wondering whether or not you guys could help.

Take, for example, this audio recording (Just ignore the voices):


And the demo recreation of it which I made:


What I want to clarify:
- The strings and choir in the original sort of "wake up", and near the end even tremble [Tremolo if I'm not mistaken]. How do I usually recreate those effects?
- I hear some kind of pitch difference between the two, as though I have the wrong octave. What is this occurence?
- I can't seem to correctly replicate the choir. What am I doing wrong?
- Would LASS and any kind of choir VST (Voxos maybe?) help solve those problems?

Thank you for your attention.

[Lavender_Harmony]

What I want to clarify:
- The strings and choir in the original sort of "wake up", and near the end even tremble [Tremolo if I'm not mistaken]. How do I usually recreate those effects?

That 'waking up' is a dynamic effect, a slow attack, where it plays to a loud point and faces back down. Later on the different elements in the string section overlap.

- I hear some kind of pitch difference between the two, as though I have the wrong octave. What is this occurence?

Your piano sound has some sort of chorus on it. It sounds detuned.

- I can't seem to correctly replicate the choir. What am I doing wrong?

The choirs are singing a chord, not individual notes like in your reorchestration.

- Would LASS and any kind of choir VST (Voxos maybe?) help solve those problems?

Not entirely no. You would still have to understand how to orchestrate a part like this out. it may sound more realistic, but without the knowledge, the illusion of using such high fidelity samples to recreate the sound of a real orchestra is broken.