I'm far from an expert so I could be totally wrong but the little bit of literature I've read on outcomes for children suggests a full time stay at home parent provides the best outcomes. That almost certainly doesn't have to be the mom specifically, but if we're going to subsidize behavior, I would prefer to subsidize whatever behavior provides the best outcomes for children. The article below suggests part time work from home opportunities with deadline based projects. That might be a reasonable answer, but again someone with actual expertise on child rearing/psychology should set policy here. The best outcomes might not be [parent] getting back to work in 6 months or even a year.
https://www.theatlantic.com/sexes/archive/2013/04/why-43-of-...
Part of what we're not talking about here (in this whole thread) is the cost of child care. Child care in SF is over $1700 a month, and hard to find for 3 month olds, which is why a lot of parents quit after leave.
I reckon we'll get a lot more parents staying in the workforce if the government helped more with childcare across all income ranges. Childcare comes at a lower income time of life, often when around when people have recently purchased a home.
We're also likely to have fewer parents drop out of the workforce if they can get their infants to 6+ months with a parent. Childcare is easier to find for 6 month olds than 3 month olds.