2500K for a sunset’ish sun sounds about right, could even be a bit lower.
But the world needs to be in the 6500K (overcast) - 20000K (clear sky) range (source).
If you choose to work with these absolutes, you might as well work with absolute intensities (although last time I checked I found different site ending up with different values) and absolute sun size of about 0.005 (to represent ~ 0.5° angular diameter). That would be accurate on the moon, but here you then increase this to compensate for atmospheric conditions - just eyeball it until the shadow softness looks just about right.
That will completely wash out the render to probably pure superwhite everything. So change to filmic for a “better” saturation response (not everyone likes it), and reduce the exposure in color management. Try this at home using manual exposure on a real camera; go outside on a clear sunny day and shoot something while adjusting exposure until you get correct results. Using those exposures, go inside your house and take some pictures. Dark, huh?
You’re using the Principled shader, which is meant to be PBR - Physically Based Rendering. So the world should be physical too to get the most out of it.
But your render wouldn’t probably change that much yet. Because we don’t have a camera white balance adjustment in Cycles. Our eyes and brain corrects for this - a white board looks white both outside on an overcast day and inside in incandescent lighting. Even mixed lighting can be “difficult” to immediately pick up on unless you actively look for it. But a camera will show you the naked ugly truth. It’s so ugly that photographers will do anything to fight it. And here we are - the renderers - the guys who will do anything to get what the photographers want to go away. It’s a wonderful world
In comp you can use this divide trick to remove tint applied from a major light source. This affects everything. So if a yellow sun shifts bluer to become whiter, the blue sky also become even more blue.
Now, that’s a lot of “science” going on… For an outdoor shot where you don’t need to consider other lights, it’s probably best (certainly less work) to just desaturate the sun (more white) and saturate the sky (more blue) until it looks good.