Look at Bugatti. He’s no longer at Hilltop but as of this March they were still selling some of his frozen semen. In his stallion test he got 9’s on character, temperament, rideability, & all three gaits.
I have a 2013 gelding by Bugatti and as well as being a lovely mover, he couldn’t be more amateur-friendly. I’m an experienced amateur (I showed my now-20-year-old up through Grand Prix doing the bulk of the riding myself, starting when the horse was 4 and with lessons from a great trainer along the way) but I have never started a horse completely from scratch before, until him. My Bugatti has been easy every step of the way. He’s also the boldest horse I’ve ever met–I had him two years before I saw him spook, and he will walk right up to/over objects most horses are afraid of.
Disclaimer: I’m no expert on breeding. Just wanted to pass on my experience, with sample size of 1. However, my trainer has said that all of Bugatti’s offspring that she has known are quite elastic and good-minded so I don’t think mine is an outlier.