Agreed Martti.

Lists:

The best feed solution in my view is user-created Lists in standard chronological order. This is how we escape the need to sort content by X, Y or Z that can be gamed.

Profiles:

When we visit someone's profile, then it makes sense to sort their notes by either date, reposts, zaps or likes. In this instance every note 'competes' with notes from the same account.

Zaps:

Highly useful as quick tips. The zap counter may be useful but there are risks that it is gamed further on since the monetary benefits from gaming a sorting mechanism are huge.

Reposts:

Indicator of content that people are willing to share in their feed. If the content is false then the reposter may take a reputation hit.

Likes:

Basic feedback mechanisms for small-medium accounts. 10 likes can remove 10 'yup' from the feed. Artists and creatives can compare the number of likes between their own posted content and get an idea of what the followers like most.