An interesting event could be writing articles like questions, dealing with cryptos - this could be search engine optimized, and thus bring people to the platform, while at the same time also being of interest to the present people!

Or a competition of writing "crypto lists"

• Ten things you never dared to ask about cryptocurrencies
• Five places to buy Bitcoin online
• 7 reasons to publish on Steem

and all sorts of similar lists... those could be cool, entertaining, and for sure draw crowds to the platform as well!