Well to give a short answer very high. Some of the greatest figures in Weimar Germany were Jewish. Walther Rathenau was foreign minister in the early 20's and was Jewish. Many of the great figures of finance were Jewish obviously with the Rothschilds having a great deal of wealth. As for the army a greater proportion of Jews served in WWI then any other group with around 12,000 dying for their country. An example of this is Hitlers commanding officer in WWI who gave Hitler the Iron Cross was Jewish. As for high commanding officers there were not that many and most of them were Bavarian and Austrian. Now comparing on what you count as Jewish means the rest of your question could be answered in different ways.

The first is if you mean people who would later count as Jewish with the Nuremberg Laws then the highest rank I could find is Major General Josef Stochmal of Salzburg and Lt General Freidlander as for practising Jews the highest I could find was a Major Max Hollerbaum.