I couldn't sell it because that would crash the market. I'd sell some of it to pay off my mortgage. I'd power up maybe seven million and become an influential figure in the Steem community financing projects that I thought deserved financing. I'd sell the rest in small batches. I'd focus on self-sufficient projects that created value and were able to generate fiat revenue independently. It is vitally important that the ecosystem have as many projects that created as much buying pressure on STEEM as possible. It is impossible for Steem to survive on voodoo economics and wishful thinking forever.
Having three-second free transfers, excellent scalability and an easy to use wallet system, Steem is the perfect decentralized platform for online games or any other such apps that deal with digital assets. I'd support projects with ambitious aims at bringing commercial activity onto Steem.
As of right now I would just keep it in my wallet.
Once the price rises up I would start to invest those in Steem Blockchain and other cryptos.
As in the current situation of mine once the price increases I would go for 50% power up.(Among those 5 million Steem I would delegate most of them to different dapps in Steem Blockchain and would allow them to grow even more and support other users)
From the rest 50% I would cash half out and half I would invest in other aspects but not in crypto while in other physical ways.
The rest would be kept in liquid and in case in future if this kind of dip happens so that I can dive back in :)
Power down half of them and ensure myself a comfortable life. Spend the other half to bring my posts to the trending page everyday :D
Sell a bunch, stockpile a few years worth of living expenses in fiat.
Strategically sell the rest as price rises, diversifying investments along the way - and figuring out some strategy to utilize the SP to reward some great leaders in the meanwhile.