Add more songs to low levels
when you reach certain levels its hard to play new songs, it would make more sense to have more songs on lower levels as optional.
Harald Thingelstad commented
I would like to have twice as many songs for when learning is slow.
The progression we have now is fine for testing things out and seeing how far you can go, but as soon as you hit your limit and just need to train and train and train (and train) to get better, the repeating of the same songs over and over (and over again) begins to feel like root canal work.
It's not a pleasure, and I believe learning should be as fun as possible.
More songs, so you can train on a song for a limited time knowing that the next song on your list is not so much more difficult that you can just as well train on the song you are at now for a while more, would be a big improvement.