To be fair, it was the Framers themselves who developped the two-party system: Adams, the Pickneys, Ames, and - to some extent - Washington being the Federalists and the Jefferson, Madison being the Democrat-Republicans.
While they did vote in substantially different ways - the splitting of the ticket between the top vote getters, for example - I don’t think they’d be overly horrified at the existence of the PARTIES.
I personally think it’s the calibre of the MEN which would horrify those early Americans.
I disagree to the extent that the Framers were very aware of factions, and did everything they could in their design to repulse this great enemy of republics.
Madison goes on at length about controlling factions in Federalist 10.
If you review Federalist 10, you’ll see that the Federalists and Democrat-Republicans of the 1790s were not factional parties.