Suggestion: Reading (furigana) in the hints in gray
I've seen many people complain about the lack of furigana over the course of the... course. The traditional method of writing small hiragana above the kanji, however, is a lot of work to implement, especially for the sake of one course; it would also spoil the pronunciation for those who'd prefer to work it out from the audio or from memory.
I'd suggest, for this reason, adding the reading of kanji in the hints for Japanese words, in parentheses, beside the meaning. It wouldn't need additional code, people wouldn't see it if they didn't want to, and, since it would be in gray, it wouldn't even confuse Duolingo's selection algorithm for the word card puzzles.
It would mean a lot of work to add readings one by one, but if the course devs are willing to make this effort, I don't want technical limitations to stand in their way.
I strongly support this suggestion. I would like to see more furigana as well as more aggressive use of kanji. I know the first course is supposed to be N5 level, but I would like to see an option for people not worried about the arbitrary levels. Furigana would be key to learning new kanji in real sentences at an accelerated pace.
I think not showing too much kanji is not necessarily bad. I for one tend to look at kanji and think about their meaning first and not always about the Japanese reading. So for compound words I can often understand the meaning but I don't always know the correct reading. Not having the kanji to rely on forces me to remember how the word is said in Japanese.
So basically it is a choice between putting an emphasis on the spoken or the written part of the language.
Even so, it is really annoying when you write answers using kanji and only the full hiragana is accepted. I guess it will improve with time but I still don't understand why it wasn't implemented from the start.