In the early years of the Weimar republic Germany had emerged from a humiliating defeat in the First World War, and hatred from the new state came from both the far left, who wanted a revolution to create a communist state, and the far right, who wanted to restore imperial Germany, stop all reparations and reverse the treaty of Versailles. I agree that the extreme right was the greatest threat to stability.
On the one hand, there was a lot of political violence from the extreme right, a significant one being the kapp luttwitz putsch in 1920, in which nationalists marched into berlin and seized control of the city with the help of freikorps, a parliamentary group made up of ex-soldiers. The army was ordered to attack them but they refused on the basis that they would not fire on fellow soldiers. This was a huge threat to stability because not only was it a direct and temporarily successful attack on the nation’s capital but it made it clear that the freikorps, which was at the time the largest army in Germany, was strongly opposed to the Weimar republic and also that the Weimar army itself had questionable loyalty to the regime, this was a huge problem and threat because the army was the most important in defending the state. Another example of political violence from the extreme right was the NSDAP, a small but vocal party which would later go on to rule Germany, who openly wanted to destroy the Weimar state and fail the people in government, the November criminals; for signing the treaty of Versailles. The NSDAP was not a big threat to political stability because they were a small party with little support at the time, however they were still a threat because of their large and growing parliamentary force, the SA, and the fact that it appealed to both nationalists and socialists could have