Mônica is great. But old Miru is indefensible getting rid of her alone justifies the rework. She was ugly, annoying. No. Old Miru is the worst. Is a statement how much Ocean improved that I know Love Miru when I absolutely hated her before. and I usually don't hate any LI.
Model wise, the old one's face screams "slut" to me, and I liked it because it fitted her actions.
The new one is good too but the face screams "young" to me, however, if you're following this for the Miru NTR Path, like myself, then she could be a dwarf for all I care.
On the scale of things, it is nothing compared to the years without progress in that said path, even before the rework.