>>24574
>They would have a lifetime's worth of "marks on their soul"
All of which they'd have their whole life to get over, and it's not like irrational phobias don't exist, if you want, you could maybe have Flashbacks/dreams about your past however those end up being depicted (if you want that to even be a thing in your fantasy)
>at the very least we'll have them hating certain ponies for no discernible reason
Hating people for no reason and getting over it later isn't suuuper uncommon as is
>or irrational infatuation with ponies they have never met.
That would probably end up being a longing for something more until you met them, at which point your soul might still love them so that opens up a can of worms, and possibilties
>(possibly ones that don't even exist)
I don't even think this one would apply at all, you'd get over that fast.