I took a quick look to see how easy this would be to add - but it is a little messy. Effectively you are asking for another "Custom Text" field - just that in your case you want to use it for a title, but someone else might want to use it for authors or series.
Which impacts multiple screens in the dialogs - adding Font option for the custom #2, big changes to the Contents tab to support it in the Field Order and an input field for it etc.
Will wait and see if others speak up in favour of such a thing, I don't have time to waste on adding features to plugins at the moment but if the demand is from more than just one person then it will be on the rainy day list.
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