My 2c on what best to do:

1) Improve the marketing for the Steem environment in other channels and media, the Steemit logo needs to be more present on other sites (like the reddit, telegram or linkdin logos)

2) To leverage this, it would be beneficial to create some incentivization for doing marketing for Steemit, e.g. by giving some delegation or Steem to people who bring new users to the platform (of course only real users who do some regular posting), or to incentivize sites that apply the Steemit logo. Money is there (as seen by the huge delegation to musing.io!)

3) New users need to be much more supported. Often they get some good rewards on the "introduceyourself" post, but then their visibility and rewards are 0. Of course many leave as a consequence. So curators need to pay attention to the follow up posts of those newbies. Also it shouldn´t be that difficult to program a bot (with some human oversight) to take care about this. This should be a standing task of the witnesses, they get payed for it.

4) On the long run it should be thought about the massive misuse of buying votes which derails the quality of the content and perverts the curation idea (If 50% of votes are bought and not given for decent content, then we can´t speak any longer about "proof of brain" but "proof of power"). If you can´t get into the "trending" pages without advertisment, then there is a serious flaw. So why not introduce a limit for buying upvotes? People with high SP would then be forced to manually vote more instead of randomly sell their VP.

5) I also would release the limit of upvotes possible only within 7 days. Wouldn´t it be technically possible to have an initial payout after 7 days, but keep the voting open and do then additional payouts e.g. monthly?

6) And last not least, the steemit frontend needs to get improved by more filtering options, search functions to retrieve old posts and a chat function. Also to have more than 5 tags would be helpful.