Hello,
I have not played this since the 90s so my memory of the game is a bit hazy, but I remember psi attacks and psi defense being a big deal later in the game, and I remember soldiers having an innate "psi score" once you get to research such things.

There is no way to know their innate psi score until much later in the game. Is there a save game editor that shows it?
If not, do you know the hex offsets? ( use hex editors and UGE)
I don't wanna actually cheat and edit the psi score, I just want to, from the beginning of the game, train & pamper my solders with a satisfatory psi score. Those with low psi will find their niche and role in life to be my scouts and.. kamikaze grenadiers!

nevermind, found everything I needed.

Perhaps you might elucidate your findings here?

Sure, I'm almost done with the game though. I used UGE (universal game editor) but you can use any hex editor
The file is Soldiers.dat, The psi strength is two bytes after Throw Accuracy START score. (the byte in between is for a dummied stat called Melee Accy)
For the first character, Psi Strength's offset i at 50 decimal. Every character is separated by 68 bytes so for char #2 its 118, and so on.

I cheated and gave everyone 70 psi strength. (Max is 100). Turns out it's a very nice, decently strong value. Aliens can still panic my units about half the time they try. They have only succeeded to mind control me once.

I don't recommend the old save game editor that came with old versions as it does not differentiate between START and
GAIN value. Every stat has a START and GAIN value except psi strength and psi skill.
For bravery START, it's increments of 10, but reversed, then + 1. So to have 40 bravery START, it's (10-4) = 6 + 1 = 7

Would be nice if the game had a "reroll stat" upon creation, like Might and Magic games and many D&D games