Great list Hive account@timcliff! Here are a few I would like added as well:

User Profiles and Badges

1. Groups be established so like-minded people can join together for better sharing and discussion of topics they are most interested in.
2. User profiles to include pictures, external post links (to instagram, facebook, twitter, etc.), optional personal profile data
3. Number of people in the group and a listing of members
4. User geography/location (can be tied to metrics)
5. User language (preferred)

Steemit eMail

1. Basic email messaging system so users can email 1:1 each other or 1:many (group emails)
2. Blocks/spam flags to limit misuse

Advertising

1. Option (opt-in for Steemians) for advertisers to pay for viewers of ads (ex .001 SBD to viewers)
2. Option (opt-in for Steemians) for advertisers to pay for upvotes for ads (ex. .10 SBD to upvoters)
3. Mechanism for authors to include ads (1 fixed bar at bottom, or something akin) in their posts and advertisers to pay authors

Metrics

1. Number of post views
2. Graphic showing number of views over time