To be honest, I love the first book, Eragon the most. The plot was moving clearly, the pace was flowing nicely, and the characters are self-explained by their actions. But starting the second book, it felt as if CP adopted a new writing style and it gradually more and more detailed, especially in the fourth book. It was moving quite slow, with many unnecessary detailed scenes (in my opinion), and... well it's just felt like dragging at times. I can't immediately see where the plot's gonna head even after many pages and we got so much input on what's going on in some character's mind - kinda like GoT books. The first Eragon, the second and the third, most were from Eragon PoV with a few exception like Saphira's and Nasuada's and Roran's. But the fourth book felt convoluted, it felt heavy. For example, CP went into so much detail just describing how Eragon fixing a catlip on a baby. Why?

What do you guys think? Do you feel the difference? And if you do and you have to choose, would you prefer the storytelling in the first book or the fourth?

You are right, his writing style changes of the course of the books. I attribute that to his young age when he began writing though. At the age of 15 (if I remember correctly) he wasn't going to drag on and on about little details but as he grew and his book got more complicated and his world grew he adapted his style so he could share what he thought would be interesting aspects of his world. Like process of Eragon healing a catnip on a baby. To him it probably wasn't just about the plot anymore but showing off his world.

Also not to mention he had other great works that are extremely detailed to compete with.