Another feature I would love would be the ability to get a printable version so I can hand it to my kids. With that it would be great to have an option for a line-by-line translation (maybe side by side so they could cover half the page to hide it) and then another option without a full translation but with a little dictionary at the bottom so they can look up unknown words.
And my preference in general would be for a more literal, word-for-word translation so I can learn what each individual word means.