Let's make first visible what 10 million would mean in Steem. Steem price is currently at 0.881 USD, so 10 million USD would be worth 11,350,737 STEEM. If you'd power everything up this makes an upvote worth 588$. 

I would personally use it just for curation (and curate fulltime) as you earn enough through curation rewards. My calculations result in weekly curation rewards of over 5,000 SP. This is a pretty good income just by curating. 

Of course you could increase your gainings by some self-votes or delegating to bid-bots and i cannot tell if I wouldn't do this in such a situation but from my current point of view, no.