Stricter With Accents
When I started using duolingo, I thought it was great that I didn't lose points for not putting in accents. As a monolingual english speaker, accents were a total mystery to me. But as I have progressed, I have found that I struggle to know when I should use letters with the accents (primarily e vs. é and e vs. è). It would be nice if duolingo got stricter with the accents as you progressed through the course. Perhaps even taking away hearts once you've reach a certain overall level or if your "mastery" of a particular word is at the max. I particularly find cognates with accents difficult to spell because I am still thinking in English. The current system doesn't aide my learning because I can always omit or guess the accents without losing any points. Lastly, I don't necessarily think this should be optional. I think once you've reached a certain point the system should just warn you that it's going to take off points for missing accents and then start marking your answers wrong if you miss them. I like how there aren't a million options in duolingo.
Given the way duolingo works (as a game, with the hearts system), I think that would be very frustrating for most users. If you want you can make it harder on yourself - keep track of how many mistakes you made and if you missed enough accents just refresh the page and start over.
You might want to check out Memrise - i use it in addition to Duolingo to help remember words. There are courses there that are strict on accents. You can also create a course for yourself for the words you have trouble remembering.
The accents are important in French as well as in Spanish, and they should be drilled in as early as possible to avoid situations such as this. Is this site to help people learn, or to give them another silly game with which to pass the time? One is the means, the other the ends. To confuse them is folly.