I’d recommend a longer full time week. If the full time week is too short, many people well rely on overtime for their salary. This completely destroys the benefits of some of your other points, since you can’t do overtime during vacations, parental leave, sick leave, etc. Overtime should not be the norm if you want a good social/financial security.
Edit: part time job should of course always be possible if your revenue allows you to work shorter weeks
Give a man food and he’ll have food for one day. Give a man a gun and he can feed himself his whole life.