I've made 100's

Solder the pins on, don't crimp.

Get a system going, cut and strip cables one day (get the Mrs to do that)

Then tin 100's of pins and all the cable ends

Then solder cables, break pins off and push into plugs

It's tedious but more than doable

I use 0.75mm2 flex (2/3 sets of plugs) into 2.5mm2 with solder join -> PSU

Otherwise you have too many cables.
I use 6/8 2.5 cables to Power all the plugs