I wouldn't go for a fin.math. or fin.eng. masters in front of a Ph.D., because of two things, first:normally they train for industry and not for academia (NYU for example states this on their homepage about the fin.math.Programme) and second: they are supersupersuperexpensive, but maybe that doesn't concern u.
And two the econ masters: The main reason why most people in this forum don't recommend this, is because the US econ masters (the few there are) train normally for going into industry or some organization directly after that. But that is about US masters, not for Canadian or European, normally. SO if u don't mind doing to Europe for one year, then just go there, maybe u can pick up another language on the fly, and then apply to US universities...or stay in good ol' Europe of course
