I have a few thoughts on daily challenges: Today my 3 challenges are all to get perfect quizzes. It also follows that if I achieve either the gold or silver daily challenge, I will necessarily get the bronze. Perhaps something that checks to prevent this from happening would be good to keep some diversity? Also, these challenges bias me to doing 10 question quizzes as that makes it significantly easier to achieve these. Perhaps it might be better to have the challenges get 10, 20, or 30 questions right in a row? This means the challenges are less tied to how long a quiz you are doing.
Thanks for the feedback. Not particularly common, but not "fun", nonetheless. It'll get easier to spread them out as I add more, but I should put in a "try and get no more than 2" of any kind of similar ones. Maybe, also, avoid having ones that overlap.
I think I can get those two things built in pretty quickly.
New rule added: Each challenge has one or more flavors. For example, "Perfect vocab quiz" has the flavor "vocab", while "Perfect quiz" has "vocab, kanji, and grammar". When drawing up new challenges for the day, two challenges that share the same flavor will never be displayed at the same time. So there should never be a situation where any action in the site contributes to multiple challenges at the same time.
Also, for the time being, I've added a testing url if you want to reset your challenges for the day. This will reset your progress, and is to be used if you want to reset it 10 or 15 times and see if this new rule is working to your satisfaction. https://www.renshuu.org/me/?chreset