For those of you who are confused, here's a succinct rundown of what you need to do:

1) Create the characters in the game's character pool (from the main menu)

2) Navigate to your Steam's workshop library and to the XcomStartingSoldiers.ini as shown below

C:\Program Files (x86)\Steam\steamapps\workshop\content\268500\1147925885\Config

3) Ignore everything that starts with a ; symbol (aka the green text if you're using notepad ++) these are just comments, everything that's important will look like what you see below:

+CHARACTER_INFO=(SoldierName="Master Chief",SoldierClass="SPARTAN-II_SS",SoldierRank=6)
+CHARACTER_INFO=(SoldierName="Terra November",SoldierClass="Reaper",SoldierRank=4)
+CHARACTER_INFO=(SoldierName="Motoko Kusanagi",SoldierClass="Cyborg_SS",SoldierRank=4)

4) Customize or Remove/Replace those soldiers as you please, just know that your list dictates how many soldiers are in your armory if it's less than 10, so don't do this just to create 2 or 3 static characters you want to have on the first mission or you'll have nobody in your armory. Also, for each soldier line that's down there that isn't in your character pool in game will be randomly generated *Nicknames are not needed but it is case sensitive!*

5) OP made a mistake on the second to last argument, just add a ; symbol at the end to close it.

In other words change this:

; Set to true if you want the starting soldiers to be removed
+bRemoveStartingSoldiers=true

To this:

; Set to true if you want the starting soldiers to be removed
+bRemoveStartingSoldiers=true;

Now for CUSTOM CLASSES, you just need their class id.
For the Super Soldiers mod I found that the ID listed in "XComClassData.ini" was the id the game references. I believe this is normally the case, depending on how the mod is applied it could be located in another spot. Frankly speaking just putting "Cyborg" or "Spartan-ll" won't cut it.

For those who are using that mod-pack in particular here's some copy paste magic for you:
SPARTAN-II_SS
Cyborg_SS
Ghost_SS
Nanosuit_SS
Ninja_SS
N7_SS

*If you don't want to make a unique soldier for everyone in your armory you can tell it to roll a random soldier as-well like I have below that way you aren't short on soldiers in your armory just add another line of (see below) for each extra soldier you need to fill out your armory.*

+CHARACTER_INFO=(SoldierName="",SoldierClass="",SoldierRank=1)


Here's how mine currently looks as I'm still in the process of creating my cast:

+CHARACTER_INFO=(SoldierName="Master Chief",SoldierClass="SPARTAN-II_SS",SoldierRank=6)
+CHARACTER_INFO=(SoldierName="Terra November",SoldierClass="Reaper",SoldierRank=4)
+CHARACTER_INFO=(SoldierName="Motoko Kusanagi",SoldierClass="Cyborg_SS",SoldierRank=4)
+CHARACTER_INFO=(SoldierName="Yvonne Stravoski",SoldierClass="Ranger",SoldierRank=3)
+CHARACTER_INFO=(SoldierName="Richard Jackson",SoldierClass="Grenadier",SoldierRank=3)
+CHARACTER_INFO=(SoldierName="Elaine Estarossa",SoldierClass="PsiOperative",SoldierRank=3)
+CHARACTER_INFO=(SoldierName="",SoldierClass="",SoldierRank=1)
+CHARACTER_INFO=(SoldierName="",SoldierClass="",SoldierRank=1)
+CHARACTER_INFO=(SoldierName="",SoldierClass="",SoldierRank=1)
+CHARACTER_INFO=(SoldierName="",SoldierClass="",SoldierRank=1)

I know it's a lot of information, but I hope this made things a bit more approachable for you.
As for other modders feel free to point out any corrections or suggestions that need to be made.

*edit*
Your starting soldiers appear to be pulled from the first 4 you have listed, I performed a series of new game runs and was able to get the same 4 as my original crew each time.