Without a defining killer app, I am confident that Bitcoin will, in fits and starts, inevitably return to its 2009 levels. It would be pointless to guess how long that process will take; or when that killer app will appear although I am also confident it will appear at some entirely unpredictable point.
I'm easily old enough to remember the very early days of personal computers. I remember a story from The Wall Street Journal in which a reporter interviewed a small-business owner (I think an auto-repair shop) who had bought an Apple II. The reporter asked the man what he thought of his purchase. The man stared glumly at the Apple for a moment and then sourly commented: "The damn thing just sits there."
Exactly. The world was just never going to buy into a command-prompt environment in a really big way. But the Mac came along and then the world began to change. (Be like the Mac! Bill Gates commanded his troops developing Windows 95.) And so it will be with Bitcoin. The world will never buy into it until an environment comes along that makes it easier, safer, and a lot more fun to use. Until then, the price will suffer periodic whale-dumps and then sort of bounce, spurt, and finally just roll along long enough for people to start talking (again) about "Bitcoin's recent price stability." And then yet another whale-dump will splash the water and the retroactively obvious cycle will begin again.
If you decide to go, then you will miss out on the killer app that will send Bitcoin to the moon and beyond. If you decide to stay, then you will watch the value of your stash just ebb away before your eyes. That choice defines your control.
As for me, for now I'm going to stay. But I've got Coinbase and can go in a second. That could happen at any time too.
[Comment added June 23, 2015:
My conclusion: stay. The blockchain itself will be the killer app upon which all other apps and bitcoins' fiat value will depend.]
There are a lot of physical tools that will severely aid in bitcoin's adoption and success. Bitcoin credit cards, ATM's, physical wallets, etc, all of which are already springing up. As for the value of bitcoin, why would it go low in the long term when it is of fixed amount? The price should increase proportionally with adoption at the least.