More calculator difficulties:
- Lux coin difficulty seems drastically lower than the actual value, which is why it's #1
- Ravencoin block reward, which hasn't changed since the coin's launch and won't for a while, is for whatever reason below 5k
- XVG is missing completely (I understand removing them during their issues with the hack, but it has been fixed for a few days now)

I like your calculator in that you can specify difficulty averages over different time thresholds, but if you can't get the basic inputs right it's completely useless.