Best Way to Design & Record the Multiple Layers of a Composite Sound?

Hi, I'm recreating this song & am about to tackle the lead stab that starts at 0:27.

Now, there are about five to six musical voices that make up this composite sound - all using different notes to harmonize it & at varying volumes. I for sure have the notes correctly transcribed, but now I'm wondering how to go about realizing each layer of the sound. I initially loaded every layer as one MIDI file a la a chord into my main synth (Synth1) & it came out sounding like a brick.

I'm thinking I may have to run one instance of the synth for each layer. If so, any recommendation on a process before I go full force? I'm imagining it'd be something like:

1) Create the patch for a single note of the layer

2) Copy & paste this in a new instance of the synth for each note in the layer

3) Adjust the volumes accordingly as they appear in the track

Am I thinking of this right or is there a better way to approach this thing? Any insight is appreciated! Thank you.