It's sad that the lady who took care of MC in his orginal world is dead here. Kind of felt like the author just wants to focus on his romantic relationship in the present, so they just had her dead from the beginning
It actually makes sense to me - in this timeline she died during the incident when the Gye family head was pushed into a rampage by the Jis. Learning that, and learning who Yoon is, gives him more emotional connection and motivation to help the Gyes and bring his own family down. (Not that they didn't deserve it in the first place.)
She was also his greatest loss in the original world, and IMO having that "fixed" (not the right word) in this one would've lessened the impact of the growth and healing he goes through.
What is their age gap?