You mean the Brüning goverment (or any substitue) would go for "keynesianism" instead of "austerity" politics ?
BTW, this was exactly what happened after the "Young"- and "Dawes"-plans. it's also in Germany called the "roaring twenties". A seemingly recovering economy fanned by (massive) public debt - unfortunatly not invested into infrastructure and industrial goods.
As it was "rendered" as one of the reasons for germanys deer situation during the Great Depression, the Weimar Goverment took the opposite way : austerity (already started before Brüning took over).
On the Pros :
- YES, it would have improved the goverments position - esp- against the commies as well as the nazis - if they would have been able to significantly reduce unemployment (by 2-3 millions), what would also reduce the poverty fears of the middle-class, who lived of the paiyd workers.
The Cons :
- where to get the money for ? Germany was bound by law, national as well as international to the gold standard (beside some other heavy restrictions on its economical and financial souvereignity), for reparational reasons as well as ... economical theorist reasons.
- Brüning thought he "needs" a suffering Germany to "convince" the Entente powers, that the reparations and their regulations have to be ended. Something much more difficult, if the outside would see a seemingly recovering german economy
Overall, the "international" situation would have made it veery difficult, to put it midly, if not impossible to implement such programs. It would need a damn awfull lot of "cleverness" to hide esp, the military expenditures) from the open sight.
As an example, how international politics meddled with such attepmts might be seen the case of the intended german-austrian customs-union in connection with the austrian-german bank-crisis of 1931.