I would choose No 2 of each of your split choices. This makes the apron 18" wide at the waist and 20" wide at the hips. That is a good taper to the apron.
These splits also result in a 6" overall taper in the pleats which is about average. 22" tapered down to 16". If you choose to to have the Kilt have 22 1" wide pleats at the Hip they would taper down to just under 3/4" at the waist (.7272"). Also very nice.

I do however wonder about your measurement of the drop of the Kilt. You state that you are 20" from waist to top of knee cap. This seems a little short to me unless you are under 5' 6". You then state that the Kilt that fits you well is 23" drop. Your Drop should be measured from the center of the top strap down to the hem. There is then a 2" rise above the strap.
The top strap of the Kilt should cinch into your natural waist which is just below your ribcage at the side.

You then state that the well fitting Kilt is 20" at the Hips and 22" at the Hem. This should not be. The pleats should drop parallel and vertical from the Hip to the Hem. The measurements should be exactly the same.

It seems you may be getting number bound. I know, I was there once myself. And I'm an engineer and used to working with measurements.

My suggestion would be to take just one measurement at a time. Or one element of the Kilt at a time and concentrate on understanding how that fits in the whole. Then move on to the second number or element.

Remember the KISS principle. Keep It Simple Stupid!!!

Also remember that until you are ready to cut away the inside of the pleats nothing is hurt or damaged. You can rip it all out, press out the creases and start all over.

It's a lot more art than it is rocket science. So don't sweat it.