Hard and soft steering

Intermediate shafts with tight universal joints are certainly a good suspect for the easy / hard steering you described, but the overlooked clue you observed was the straining power steering pump. Most people would have missed that. That is the result of the steering linkage not moving freely. If the steering input shaft was binding, the steering gear would just sit there with little or no input from you, and as far as the pump is concerned, it thinks you're just sitting there at a stop light.

Given that extra clue, a better suspect would be a tight ball joint, in this case a lower one as those are the "load-carrying" joints that support the weight of the vehicle.

This article:

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

is really for the benefit of others researching this topic, but in addition, the best approach is to place jack stands under the two front lower control arms and set the car down on those rather than under the frame rails. This will cause the suspension parts to go back up to their normal at-rest positions. Often that is the only place where tightness shows up in a ball joint.

With the steering wheel unlocked, you should be able to turn the front wheels left and right with some effort, by hand, right at a tire. If you feel the binding, you only know one of the ball joints is tight. You may have to disconnect one of the outer tie rod ends so you can turn each front wheel independently to figure out which one is tight. With the steering linkage disconnected from one spindle, that wheel should be very easy to turn left and right with one hand. In fact, it's common to find it flops outward at the front of the wheel / tire just from gravity as it sits on the jack stands.

Let me know what you find.