I have a feeling that most folding bikes will actually fit you OK. If you were 4' 10," it'd be a different story....

If you're planning to do fairly short distances when you travel, I recommend you go for a Brompton. You can get it onto a plane with almost no disassembly, it's got suspension, and is great for commuting. Check with your building to see if they will let you bring a folding bike into the building -- you don't want to leave a nice bike on the street in NYC if you can help it.

Bike Friday makes excellent bikes, and while the "quick fold" is just OK, it is made to pack efficiently into a suitcase. But the Brompton will still pack faster and easier. A BF may also be overkill for your uses.

Unfortunately there aren't many "ridiculously light" folders out there except for the really tiny ones, like the A-Bike -- and even that is 12 pounds. Most folders don't have a traditional diamond frame design, so they need heavier frames to compensate.