The first horse I trained to jump was a Pilot great grandson (through Pidgley, a son of Pilox). If I’m being totally honest, though, I put the flatwork on him, and he taught himself to jump. I was told he had a typical Pilot-descendant personality, which was definitely on the quirky side. Very talented, very athletic, and once he understood his job, he was very reliable. So despite being difficult to start, there was a really good brain for sport in there. Also very lovable on the ground. He was best-suited for stadium jumping.
I wouldn’t necessarily call him spooky, but he was tricky for most of the year I worked with him. He really objected to being off-balance, and he would take advantage of me and toss a buck if I were off balance. He also bucked on landing if he rubbed a fence. All of this went away over time though. He insisted that I ride correctly, which I loved, but yeah it was tricky. He made me a better rider and a better trainer.
There was also a closely related Pidgley daughter nearby. She was a little more naturally balanced than the gelding I rode, so she might have been easier to start. Her owner/trainer was male, and having a little more physical heft may have helped him too. I don’t know what she was like when she was totally green. I mostly saw her in jumping lessons, and he just pointed her at jumps, drove her straight at them and let her take care of the rest.