Part of the magic of RE4 is that you can tell the developers squeezed every last drop out of the gameplay as they could, which led to sequences like the minecart and the minigame. It's an everything but the kitchen sink approach to game design that you don't often see anymore because nowadays developers save those ideas for a potential sequel. It's probably why 5 felt so much less interesting than 4 in hindsight, but it makes 4 feel like a huge, crazy adventure. And that approach can be seen in the game's fluctuating tone, going from tense and disturbing in the early hours to goofy and over-the-top once you get to the castle. I can see them cutting things out for being tonally off, like Salazar's castle, and maybe making the entire game focus on backwoods horror in an infected village.
I can easily see a modern remake try and streamline everything to make it a more consistent experience, and with how the recent remakes have been I can also see them trying to swing for a more horror-centric game than the original was. I suppose we'll just have to see, but either way the original game was lightning in a bottle and I'm skeptical a remake can even live up to it.
