This might sound obscene, but how about using noise reduction software? I stumbled across this "hidden" feature when I overprocesses some noisy images as a joke. With Neat Image, for example, you can retain high frequency "noise" (=focus plane) and suppress mid and especially low frequency "noise" (=bad bokeh).
Of course this is no serious method, but for an untrained or trustful eye you can turn a FA43lt/f4.5 pic to a FA31lt/f1.8. At first sight.
Just as a proof of concept some quick and dirty "noise reduction" with some examples from this thread. (I didn't use the "bad bokeh" example as it has no focused area, so this makes no sense as one could as well just use a global blur filter)
one:
two:
three:
You might see that there is also some slight loss of detail. Which cound easily be improved with Photoshop and some layers.
C&C is welcome!