Proportional representation doesn't have involve voting for parties (party list proportional is one mechanism for achieving proportionality; another method for acheiving proportionality is using voting systems like Single Transferrable Vote in multimember districts -- the latter method is just as candidate-centered as the FPTP-in-single-member-districts system used in the United States, yet provides proportional results [the degree or proportionality varies with the size of the districts.])
While its less proportional, in partisan terms, than party-list proportional (assuming usual sizes of legislatures and manageable numbers of seats per district for STV), it counterbalances that by being more sensitive to general election voter concerns in selection between candidates of the same party.
> The FPTP system we have is a reflection of the framers' desire to avoid parties.
No, its not. The framers were familiar with FPTP, and familiar with the way that parties operated under it. It wasn't a new idea that they were trying out expecting that it would avoid the formation of parties.
It's inaccurate to even say that "the framers" had a coherent desire to avoid parties -- Washington certainly did, and this certainly got more urgent for him as the First Party System took hold during is term as President; Hamilton may have initially opposed parties in the traditional democratic sense since he was more inclined to a life-term aristocracy (remember that he wanted both Presidents and Senators to serve "in good behavior" -- that is, for life subject to impeachment -- the way that in the Constitution-as-it-ended-up federal judges do), but he seems to have readily accepted political parties as the second-best choice; Jefferson clearly saw parties as an inherent part of democracy, and the absence of parties as a feature of despotism, and actually seemed to see a two party system divided on a particular axis -- which he referred to as Whig v. Tory -- as fundamental and inherent in the nature of mankind, though he also was clearly opposed to tribal adherence to parties.
You are confusing "proportional representation" (which is a continuous-valued property of many election systems) with "party list proportional" which is a particular election system for achieving a high value of proportional representation.
Notably, Single Transferrable Vote is a system in which people vote for candidates as they do in FPTP elections (except using preference ballots), but which is designed to acheive proportional representation.