Thanks for your suggestion.As with the active key, I have already tried to explain why it's safe. My source code is open on github. Hackers wouldn't put their source code on github for everyone to see and the tool runs straight from my github's repository! As with the fee, I'm not sure if the tool can manage that many transfers! Ideally, you wouldn't want to tip that many followers anyway which is what the active filter is for. I might add another filter which would reduce the number of active followers to those who have upvoted and/or commented on your post instead of steemit in general. But thanks for the feedback. I will definitely consider it! :]