Display number of words due?
I wonder if it would be possible for us to see a total count of how many words we should review at any given point? For example show the number of words that have dropped down to two bars, this way as you practice you can see the number of words decrease, which for me at least would definitely be a motivating factor. Even if you get all your skills to gold, there are still words that are already at the point that they should be reviewed. This is part of what keeps me motivated on Anki to keep going.
The Vocabulary feature used to do this, more or less - you could sort by weakest/strongest words and it had a "Practice Weakest Words" feature that could be useful for review.
It didn't have a running count feature, though. That would be an interesting statistic to expose to users, I think.
However, the recent redesign nuked the Vocab tab. Supposedly it's coming back in a new-and-improved format sometime soon, but it really shouldn't have ever been removed from the site!
Yah, I've been around Duo a long time lol. They said people weren't using the vocab feature to make it worth the structural work that it required so they're finding a more efficient way to implement it.
I just think any statistics that would motivate users to keep going would be helpful. But I don't know if that number would be more or less motivating for the average user.