Keep a day trip focused on Gwalior Fort
A same-day return suits travellers who primarily want the fort and have an early Agra departure. Leave time for road delays and plan a smaller number of sites. Avoid adding a second city or tight onward connection.
Use the overnight for a second theme
An overnight gives you a separate block for Jai Vilas Palace or the Jain sculptures rather than forcing both into the fort day. Check opening days and choose one that suits your interests and walking pace.
Check drop-off and steep approaches
Ask which parts of the fort or sculpture route involve stairs or steep slopes. Confirm whether you return to Agra or finish in Gwalior, whether the hotel is included and how any station transfer is timed.