My view on folding bike design in general, and particularly with Brompton, is that the stem/steerer interface hasn't been properly addressed such as to maximise stiffness. Tern said it was a priority for them but I don't think their solution was good. The problem with solving that issue in relation to a Brompton is that the amount of flex in the frame and particularly in the stem/steerer interface has a softening effect on what would otherwise be a harsh ride. So I think that the issue of flex has to be addressed in conjunction with improving suspension, probably through the option of wider tyres (305 Big Apples are really good, bouncy but nimble) though perhaps with mechanical suspension. I don't think Dahon has addressed any of these things, but nonetheless I think that competition will increase the likelihood of improvements in these areas.
The bike you posted pics of doesn't have a very compact fold since the chainring juts out. It's not a great design.