is Voronoise good enough for your purposes? https://en.wikipedia.org/wiki/Worley_noise#/media/File:Worley_Noise_F1_Normal.png (maybe not max slope everywhere; some places have less. but I prefer for the edges to look smooth like there was anti-aliasing done. and it should be ez to make adjustments, like doing some number other than one per cell, or just go into a sculpting program, take cone shape, poke a bunch to varying depths, then switch to the other side of surface to alternate sessions of drilling down and lifting sheet up)

I was planning to make a variant based on an idea I had https://drive.google.com/file/d/1jEMadwTj8kt0QOzcHxghZsLKQevwXL6Y/view?usp=sharing (ignore the part about constant-height rollers) since I actually need the limited slope property for smth (I thought it'd be interesting to take a (~slanted(tilt sounds like I'm starting from horizontal) plane. wanna go more ambitious than pure vertical)2D slice of 3D terrain and see if that "slant" makes it so that even I took cross section from basic version that had all ~mountain peaks at same elevation, artifacts won't be as noticeable). https://www.reddit.com/user/Educational-Force776/comments/1apg3r4/randomly_generated_cliffside_path/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button designed so that not just the isometric view, but even from different angles, there are no overhangs. it's like being able to rotate a sine wave less than 45deg and creating smth that isn't quite like its (rotated 90deg) inverse function which could only keep one cuz for functions no two outputs can share the same input