As already said, the quality will keep on improving. As is the case today ... its less "modelling" and more "assembly". I see the focus moving further over to painting and finishing (this is already true), and hopefully this keeps developing as well. I could see kits coming with less parts in the future so assembly is faster. As moulding technology and 3D printing develops, this would be an obvious direction. Technology exists to day to insert ... say ... etch or another sub-assembly ... into a newly moulded part in production, but I canīt see model manufacturers going down this road as sales would need to be a lot higher.
A friend had a very interesting point a few days ago. One of the biggest issues today is bad instructions. Why donīt companies issue these instructions online also, in digital format .. in bigger resolution ... so that when faults are found they can quickly be updated, and a FAQ type sheet with answers that arise from each new kit. What a resource this would be to modellers, and quell a lot of the problems we have today. This is something companies could do already today!!
I think there are kids in the hobby today ... just not as visible. The local games workshop has loads there at weekends painting like crazy. If the assembly time is reduced and painting is started faster .... with newly evolved or improved methods/techniques/media, some of these kids might cross over? The gaming generation might get bored with tv simulations and decide to create and hold the armor in their hands, rather than see digital versions on a screen.
The thing needed most for the hobby to expand is exposure ... exposure to these kids and those who want to try something creative. The sad thing is that the local hobby shops are closing down as they cannot compete with online retailers. Toyshops donīt carry models much anymore as they are so advanced, they are not really for aimed at kids. Magazines are getting very expensive and not something you pick up a few of regularily. So how will the hobby be exposed to others ... today and in the future?