If we increased this threshold up to 0.10 SBD, or even 0.25 or 1.00 SBD - then posts/comments that did not receive sufficient votes to pass this threshold would receive zero payout. This would likely decrease the incentive for users to create spam.

This is baddest idea.

I cannot agree with this. This is another way to say goodbye to new users or users who don't have much steempower on their account. Do you think it's eays to make 0.1SBD for new users?? I am here from last july and till now I could only accumulate around 2000 SP with more than 1500 followers, I can't even make 0.5 SBD from organic upvote including my self-upvote. You can simply imagine the situation of new users. they have already made this place a botland and most of the big users even witness has massively involved on vote-selling rather than giving organic vote for someone.
First, propose something to improve this situation rather than putting a threshold. Or you guys already has had enough of users and don't want more from inside???? This will only affect the real users or new users and spammers and circle jerkers are still safe.