I keep thinking that I need to find a way to throw some water on this fire before someone gets hurt, but the only way I can really do that is to sell some MSC, which I don't want to do at these prices

I hope everybody isn't buying now with the intention of selling when the distributed exchange opens. If so, that very positive news for MSC could actually be correlated with a price drop!
Be careful folks.
Is there a way to encourage a more diverse group of people to buy smaller proportions of MSC? I saw Realsolid do a thing where he limited the amount of Feeshares that anyone could buy at one time. I think that is something maxmint could do to put the fire out a bit.
I was trying to organize crowdfunding for Netcoin and the plan was to do something similar. So basically if the orders are limited to being below a certain BTC amount per order then you'd have a more widely distributed MSC. We want as many people holding MSC as possible.
So Luckybit wants to buy MSC and the limit anyone can spend on MSC for the week is 10BTC worth, this would limit Luckybit to 10BTC worth of MSC no matter how much MSC is going for at the time. This prevents Luckybit from being able to buy enough MSC to dump it later or from spending his life savings on it.
Workable solution?
Another solution, instead of selling MSC it might be a good idea to start up a MSC faucet and give out small quantities like (random lottery amounts .1 , .2 , .3 ->.9 ) of MSC for free to people. This way the people who already purchased MSC wont suffer as much but MSC would also be distributed a bit more.
Who wants to volunteer to start the first MSC faucet to put this fire out? I don't have enough MSC to do it.
the only way I can really do that is to sell some MSC, which I don't want to do at these prices

See above:
That was a very big mistake. Might as well just throw 100 Euro notes in the toilet.
Open markets are good. Market manipulation almost never goes well or produces the intended result.
We don't need no water, let the mother F-er burn.
I think it's in all of our collective best interest if as many people as possible are holding MSC. If that means starting an MSC faucet thread then we could use that thread to spread MSC around so that more people have a stake. The other thing is we could do is limit the amount of MSC that any single individual could buy and prioritize new purchasers so as to reduce the ability of any individual to dump MSC upon the launch of the decentralized exchange. If thousands of people have 1-2 MSC that is far better than if hundreds of people have 100-200 MSC.