Well, perhaps when you guys start working on 2.0, perhaps OGRE could be intergrated into the rendering engine? If anything, it would work for future 3D rendering, and perhaps the effects that come with it could come in handy, if nothing else... Construct + OGRE would be awesome.
Still, I can imagine that the logical steps Construct could take eventually are 3D graphics with 2D gameplay, then completely 3D gameplay. The latter would take a lot longer than the former, I gather, and probably wouldn't even be touched until Construct reaches the point where there's no other direction to go in development, methinks.