What things most surprised Mollie-as-Gerald?

The thing that most surprised Mollie-as-Gerald was the fact that the woman could not get close to her baby boy. The woman was suffering from postpartum depression, as she did not even have the energy to put on her dress.

What most surprises Mollie-as-Gerald is the differences between a woman's life and a man's life.

Explanation:

Mollie has always been a very dedicated housewife, but her biggest dream was to be a man.

When she becomes one (Gerald), she begins to see and understand things in life that she had never been able to understand while at home.

She was surprised at all these new aspects. From simple things, like having pockets, to having power over her own money, her own work, and all the possessions she now had, without having to beg anyone for them.

She was also surprised to discover how the talks between men really were, and how they had a double thought that they did not share with women.

And that way, Mollie as Gerald was learning more and more new things that were surprising her.