Definitely agree with you here. I can't tell you how many times I've watched weekend warriors at Vail take waaayyyy too much speed into a 10 foot jump and send it to flat.
Aside from jump shape I think a very important part of safe jump building is establishing a starting point so the speed can generally be figured out for those who don't have the experience yet. If you build a 10 foot jump with a 100 foot steep in run beginners aren't going to know to start lower or speed check before hitting the lip. The way parks are being designed these days most people assume the starting point is the starting point and you can just go from there. Some parks do a really good job of this with bigger jumps but this method needs to be used for all size features. I think everyone can agree that speed checking 10-20 times into a jump isn't as good as making a few turns and catching the landing perfectly. Speed management is also key for features in a row. When you can land a jump and just cruise into the next one it is a lot safer and smoother. When you have to speed check a lot in between it creates bumps and uncertainty. Same goes for not enough speed. Its sketchy having to land perfect and then point it into the next hit.