That was a gorgeous P-38 grandchild. Too bad COIN, which frankly given the geopolitics of the OTL postwar period strikes me as the guys in black hats far more often than not, would be the main mission.
How to have an insurgency that deserves countering? Mind I recognize that a whole bunch of them that have the right enemies to be good guys nevertheless are not--this applies on both sides of the Cold War ideological divide too. At the end of the day insurgency is a dirty business; the trouble is the parties of property and order are typically just as dirty.
So who would be bad guy insurgents? Basically I'd think we'd have to blow WWII, leaving the Axis sitting pretty after some sort of white truce in which Hitler owns Russia and so forth, with all the horror that portends, and then we have them projecting power, perhaps via ultra stealthy U-boat landings, in the soft form of aiding fascist insurgencies in Latin America and the Philippines. In short screw the pooch in the 1940s, in order to play the beleaguered boy scout hero in the 60s. And even given the global setup I so pessimistically offer, which is Thank God clean out for this ATL with the Axis on the run, it is most likely to boil down to a noir sort of story of hats of various colors of dark grey with variable size and sources blood splatters all over each, no Boy Scouts to be found. Or to be found but the kind Tom Lehrer sings about.
I have a complete schizophrenic split between the gorgeousness of airplanes and the sort of missions they are meant for; let's face it, by and large civilian operations rarely call for beauty. Or we don't see the beauty of a conventional tube with wing & podded engine layout because it is so mundane--a Lockheed Constellation had gorgeous lines to be sure. But it lacks the sort of rakish look of a true thoroughbred performance plane. The DeHavilland Comet was a pretty airplane too, but part of that related to why it proved uneconomic even allowing for it being crippled by an unforeseen engineering error--with the engines buried, upgrades were quite difficult to manage, and I suppose routine maintenance was more difficult, slower and more costly too. DeHavilland in general often achieved planes that were gorgeous as well as of iconic functionality--such as the Mosquito. But in the jet age, one of the greatest economic assets of converting to a jet fleet for an airline was that turbine engines needed less maintenance time, and turbojets less than turboprops. They also were quieter from a passenger point of view and faster than anything not specifically designed to go supersonic. Even if the Comet design had been perfect from the get-go its potential was limited by the buried engine philosophy--even if that had allowed them to go faster and be quieter the difference in maintenance costs, and lower flexibility as to engine upgrades would always be a drawback.
I suspect that the greater isolation of the engine in a podded design was offset by its noise radiating freely through the air around the overall noise profile for passengers would have been a push, the noise in a Comet being more a matter of stuff transmitted through rigid structure FWIW, so for passengers there would not be a sonic noise advantage, though the Comet, in a given state of the art, might be quieter for bystanders. The problem there being that the Comet being an early generation design which could not be sustained to 1970 or so always had early state of the art engines--turbojets were inherently noisier than turbofans, and early versions needed thrust augmenting expedients for takeoff including for the Comet built in hydrogen peroxide JATO rockets and later water injection--all of these were noise issues as well as the latter producing infamous trails of soot. Trying to get buried turbofans into a clean sheet late '60s Comet derived design would turn into a nightmare I would think, though if anyone could tweak the aerodynamics to make it worthwhile it would be DeHavilland. That company did not exist as such by 1970 though.
Anyway pretty and functional are often not the same thing, and with the development of the jet engine the basic Lightning design became--well, still a major thing in the hands of none other than DeHavilland! But Vampires and their Vixen derivatives, though apparently functional, are quite goofy looking jets. Anyway you didn't want an American Vampire, you wanted a P-38 layout descendant that looked good the way the Lightning did, and for that it requires a military mission, and in the jet age there is not much call for a prop plane for the romantic stuff like interception or strike escort; it comes down to roles like COIN.
To some mentalities that is romantic enough I suppose. It just makes me sad though.
If only Just Leo were here, he could paint it up in California Highway Patrol colors and do one of those funny "Traffic Regulations Enforced by Aircraft" pictures...