Brandon Sanderson
I think short chapters do some good, and accomplish a lot. Martin is a master, and he uses them well. (At least, in some places.) Pratchett does an equally good job at it in a different type of sub-genre. But used poorly (or, well, unfairly) they do some terrible things to me as a reader.
An example here for me is Dan Brown. I don't want to pick on him, as big targets are often too easy to pick on. He's obviously been very successful, and has some very interesting things about his writing. However, one thing I noticed reading the Da Vinci Code was that he seemed to be using the same tricks over and over and over to simply get me to turn the page. Someone would open a door and... We don't find out what was on the other side. The chapter ends. We go to the next chapter, and we either find out that nothing really that important was on the other side of the door, or we get told "I'll tell you what was on the other side of that door eventually...if you keep reading."
This actually works, quite well, for a little while. (For me in the Da Vinci Code it worked for about half the book.) And then, it just gets wearying to me. The gimmicks start to show through, and I get tired of never finding anything out. There doesn't feel like development, just one big long stall. Yes, it's possible for a book to be "too exciting." Because if excitement is all there is, we lose character, setting, and a whole lot of depth. We go from trouble, to trouble, to trouble. High tension moment to high tension moment.
Now, this is an extreme example, but I think that it's something for writers to think about. You suggest that self-indulgence is a danger. Yes, perhaps it is. At the same time, I'm not writing thrillers. I'm writing epic fantasy. I'm writing 300,000 word plus books. There should be ups, there should be downs, there should be moments of frantic pace, and there should be scenes of (yes) dinner. Sometimes, the most telling scenes in a story can be a simple dinner sequence. The scene with Faramir riding to charge while his father eats from the LoTR movies comes to mind.
But this isn't exactly what I was trying to get to. I write long chapters not to (hopefully) indulge. I do it to make each chapter (or sequence of them) to have its own rising action, its own climactic moments, its own falling action. I want to open the door and, instead of cutting away, show something on the other side that really does upset the scene. Then continue through the scene to show the ramifications. I want to have each chapter be a story unto itself, rather than a movie trailer for the next chapter. (Which, in turn, is a movie trailer for the next one...and so on.)
Again, I do think there are great ways to use the short chapters. But I worry that the conventional wisdom of "Don't ever let them put the book down!" is bad advice for some authors. Les Miserables has a whole lot of parts that are not very exciting. There are plenty of parts where, once I'm done with the scene, I can put the book down and walk away. It pulls me back to read not because it uses a cliffhanger at the end of every chapter, but because the deep, rich characters draw me back to read further about them.
I do agree that the larger casts are a problem that doesn't seem to have a good solution. Either you ignore half your characters for a book—as GRRM did—or you give them only brief appearances—as Robert Jordan often did. I don't think I'm in a position to criticize either author as, unlike Dan Brown, I think they both do/did fantastic jobs with their works. But I am consciously keeping the cast of the Stormlight Archive down.