Personally, I'd like to see Esther being the lucky one, she has much more chemistry with Max, they interact much more normally and she's overall a kind and cheerful person.
But she's not the main heroine, so chances are low that she will, well, make it in the end.
The ex-girlfriend doesn't count. It doesn't even play the same way that you would expect from an actual love triangle. She's essentially a narrative tool for the MC to sort out his past transgressions and unsorted feelings. And as per latest chapters, he did.