Considering that and your requirements, it's either Brompton or the 16" models from OriBikes. Since you have the money and you'd rather a shifting hub, consider OriBikes' Mi8 City.

Since OriBikes is in Taïwan, you should check 'em out. Ideally, you can find a store that carries both Oribikes and Brompton, so you can try both and make an informed choice.

Edit: Video that shows details + (un)folding.