The onboarding perspective would be the reason to change the threshold. 15SP is delegated by Steemit to new accounts, but around 25SP is currently needed to reach $0.0005. So from that point of view, it would make sense to lower the threshold.
Maybe we should make a dPoll about this and let all the users choose.
Three options:
- No change
- Remove threshold completely
- Set threshold to 10SP