The Handmaid's Tale is a brilliant example of a story that ends with questions unanswered. What happens next to Offred? But Margaret Atwood couldn't resist adding an epilogue, exploring further. And then she had to write another book because readers kept asking what happened.
I was delighted, when I first read The Lord of the Rings as a teenager, that Tolkien added a whole book's worth of appendices, explaining everything including the fates of all the characters. I couldn't get enough of it. But in the case of an entire fantasy world, history, religion and linguistics, that is probably allowable.
So when you reach the conclusion of the drama, how many lose ends should be tidied up in a conclusion? The prince wakes the princess with a kiss. Is it enough to explain that they get married and live happily ever after. Do I take it further and discuss what that happiness involves, how many children they’ll have and what medical conditions will finally carry them off in old age? Or do I stop with the prediction of their marriage and leave the readers to guess if it’s likely to be happy or not? Or do I leave it to the reader to assume that they probably get married, because the kiss is all that’s needed to end the plot.
I am inclined to think that less is more. End with the kiss.
(especially when the original story goes on to have the prince raping the princess in her sleep, leaving her pregnant with twins whom his mother plans to eat.)
My usual solution, probably like many other authors, is to add a chapter, slightly detached, as an epilogue that wraps up most things just sufficiently to answer the obvious questions while leaving others unanswered.