As I see matters, holders who can be scared into selling have already sold so I don't expect them to drive prices down from here. Those (like me) who buy as the market moves lower are now mostly fully invested, so we're not putting very much new money into the market now to drive prices higher.
That leaves as the primary mover of price the interplay between miners and new investors.
Miners will not make new coins available for less than the price of electricity to mine them plus amortized hardware cost, so I don't see miners selling coins for under $400-$450 anytime soon; under $450 they can't pay for their existing hardware, and under $300 they can't even pay for the electrical power. Some of them will gamble by pointing mining rigs at the altcoin markets to try to get some leverage on that expense rate, but the underlying equilibrium is driven by Bitcoin. As measured in Bitcoin, the alts are essentially an artificial options market where every winner has an equal and opposite loser. So there's not a long-term winning strategy there unless you're just plain better than average at picking the right time to mine the right alt, and because "better than average" implies the existence of equal and opposite "worse than average" the effect of alt gambling on bitcoin prices ought to be neutral. So, based on the miners' expenses to mine, I'm seeing the current price as a supply side bottom and an excellent buying price.
So, finally, the remaining potential price mover is new investors. New investors can't drive the price down, but they can drive it up. How much? How fast? It depends on what they want to do and how much bitcoin they need.
I'm particularly interested in new investors who want to use it as a payment medium because that kind of investment gives bitcoin a sustainable value. But they're a bit hard to predict in terms of effect. The amount of bitcoin they need is inversely proportional to the speed at which they can move it around their systems, and although the ten-minute blocktime does impose a "soft" limit, they're already quite experienced moving fiat currencies around in conditions that are very similar to bitcoin moving faster than that limit. The problem with that is, when moving bitcoin around faster than that speed limit, they don't realize any advantage from bitcoin's decentralized security network, so at those speeds it's not any better for them than dealing in fiat. They want to move the coins around *slower* than the blockchain speed limit if possible, to mitigate risks and minimize expenses allowing them to realize an advantage from bitcoin, and that means they need more coins.
There are also traditional investors who want to use it as a store of value. They are drastically more dangerous in terms of making the market unstable. The amount of coin they need is easier to guess at, but they're sweating bullets about SEC regulations, potential lawsuits, and repercussions. Bitcoin is a fairly small and very artificial market. If somebody who has put together a mutual fund including bitcoins moves ten billion dollars into this market this week, of course the bitcoin holdings of the early holders will double, largely at the expense of later investors. And the following week, they can do the same thing again with more money providing a handsome profit to those who invest this week, and so on... moving the bitcoin price up at a superexponential rate until it collapses horribly and they wind up facing lawsuits about Ponzi scams and SEC fines about market manipulation. They want in, but they are terribly afraid of the results of the Ponzi-like effect they'll have on the market when they get in. They need a strategy that gives them some kind of agreed-on rules about how to get into the market without becoming its primary price drivers and therefore inevitably inflating-and-collapsing it.
Anyway, I don't know how they're going to work it out. If the store-of-value investors adopt a strategy of holding no more than, say, a tenth of what the payment-processing investors hold, then money will enter the market at some reasonably controlled rate and they probably won't become the effectively-a-Ponzi-scam that they justly fear becoming. But I don't know if they can do that, and whether they can or not I don't know whether they can accurately assess their ability to do that.
That is one wall of text!
Protip for next time, add a tl;dr.
Thankfully Kiki did that for you already!
But it was a good read, thank you.