Wow @happyme, thank you very much for your investigations and the great feedback!

You are absolutely right, the slider should automatically jump to the correct position in case of typing in the value manually. That's now on my list for one of the next updates ;)

I will think about your other points over the coming week. Having kind of a threshold for the minimum payout amount could really be a very good solution. It's not so easy to implement, because the beneficiaries can't be changed after creating a post and the account @steemworld.org would need to send the rewards back to the author after payout, but I like the idea.