Feels so weird that they had to add filler to get more screen time, as when reading Witch House it felt like a lot of time has passed in my imagination :D

But remembering the story, it actually totally makes sense that when adapting it as a movie, it would be hard to get much to show for longer time. Didn't think before that adapting something from text to movie could cause such quirks! New perspective to see things from

How about The Dream-Quest of Unknown Kadath? I've read it recently, and it seemed to be pretty focused around the character. Although original story is a bit hard to follow at times leaving much of descriptions up to imagination, with adaption it could really fit well into a movie in my opinion

Lovecraft has other various stories which are pretty different from that. He even wrote sci-fi story with interesting take on future for the times