Digest of Tips and notes?
I'd love to see a feature that digest all of the "Tips and notes" section that you have seen so far into one page?
Maybe with a PDF download feature? Something I could print and markup/annotate on the train would really help cement the lessons in my mind.
There are resources elsewhere on the web that you can use to do the same job. I use Wikipedia's pages about languages' grammar, e.g. https://en.wikipedia.org/wiki/Italian_grammar. They're quite dry, but they're precise, and useful.
There are links to some useful grammar resources on the Duolingo Wiki, e.g.: http://duolingo.wikia.com/wiki/Italian#Grammar_references