Easy to reach, still a real decision
Nara is often treated as an automatic half day. That works for many trips, but not all.
When a day trip is enough
Choose a day trip for the park, Todai-ji, a few walks and lunch without adding another hotel.
When overnight is better
Stay overnight if calm evening, early morning or slower family pacing is the main value.
Children and pace
Nara can be easy with children, but deer, heat and temple walking make pacing important.
Choose a clear role
Either keep Nara simple or give it real time. A late arrival and early departure rarely adds much.