honestly I dont think it is approiate to compare them in sense of 待遇和出路...........
given that a master is required for admission of PhD in Switzerland, the applicant are supposed to have some solid idea about the field that one have the research interest, just like a PhD student after the QE.
my short answer will be: this is not a question of concern, just select the one that one is interested in.
P.S.
Normally, econometrics are considered as one of the subfield / concentration under a economics PhD, so that a PhD student in econ are select it at some time point. But given that it is a seperated program existing.....I doubt if the econ PhD student can select econometrics as the research directly without any adminstrative trouble.