I can't see why prices on a lot of loose and MOC won't at least double over the next 10 years, the common stuff maybe not so much.
But like a lot of people have already mentioned lately there's a lot of value in MOC's at the moment too, some loose figures aren't actually too far away from what a MOC costs. Take Lumat for example, loose, complete & mint you're looking at about £50, but MOC in decent condition iv'e seen go for like £80 a couple of times, just an extra £30 for an untouched sealed one on nice condition card?, there's great value there. And a loose AT-ST driver mint & complete £35 - £40, yet MOC you can pick up for about £60+
I think MOC especially has a much longer way to go yet when more and more collectors start taking advantage of carded figure prices, I can possibly see MOC values rising more than what loose will over the next few years.