Conservatives get all whipped up about what the GOP "hasn't done," without remembering it is precisely the intent of the Constitution to force groups/factions/parties to come back, year after year, to build bigger majorities for a change. Aside from the Civil War, when fully half of the Congress---and virtually all of the opposition---was gone, and the Great Depression, where the mandate for "doing something" was so great and the majorities so large, it really takes about 40 years to get important issues acted upon. The Great Society was still needed by the Dems DESPITE having the FDR blitzkrieg 30 years earlier.
I would say there isn't much in the constitution about political patronage, entitlements, pork barrel spending, gerrymandering, and so-called "campaign finance reform". As for the bicameral legislature issue, that does slow things down a little, but not as much when you have a President in the majority party and not as much when you have extra-constitutional senate rules to contend with.
Thought you'd enjoy this post no. 71 by LS, which adheres to your old and steadfast theories of American politics. I can only add to LS's post that it's impossible to define and measure what has not happened , which is the very largest of the GOP's accomplishments. (For example, I credit Taft with halting the worst designs of the progressives; we could view every other post-Civil War era in the same light.)
The genius of the Founders lies herein, and you, LS, and x are the most very aware FR advocates of it.
All the best to you, CT!