You have several practical problems with huge engines. One is that the Market for them winds up being on the small side. You need a fighter the size of an F4U or P-47 to handle even the P W R-4360. How big a single engine fighter do you need to hold a 3 ton engine? The same sort of holds true for twins. Pre war twins were often under powered form a safe fight point of view. A number of Pre-war and early war bombers could not maintain height on one engine even with the bombs gone. THings got better with more powerful engines but a with these monsters there was a risk of going backwards in the sense of using two 5000 hp engines vs four 2500hp engines to power a large plane. If the 4 engine plane looses and engine it is still in pretty good shape, if it looses one on each side it may still go a pretty fair distance to land. The really big twin loosing an engine is in serious trouble. 1/2 power and a powerful asymmetric thrust requiring drag producing "trim" on the controls. A small but high powered twin may have surplus power but the weight and fuel consumption of these engines tends to go against a small twin. yes you could have 7-10,000hp using engines in the upper part of the list but you also have 4-6 tons of engine weight, some really big propellers and the ability to suck up 15-20 gallons of full a minute at full power. You aren't going to stick a pair of these things in a Mosquito sized airplane or even an A-26.
The monsters only make sense on planes that will require 4 or more of them and those are very large aircraft indeed. And as such are not likely to be built in large numbers.
The next problem is transmitting that kind of power. You not only need the engine but you need to push propeller technology and reduction gear box technology to their limits to get the big engines to work (you also need big landing gear to get the props high enough off the ground.
Getting serious again, most everybody vastly under estimated the difficulties in building and running these large engines. We have the benefit of hindsight from 2015 but just as an example, P W used many more test engines and spent about 5 times the money IIRR on developing the R-4360 than they did the R-2800. The problems
seemed to rise exponentially with the number of cylinders.