I wouldn't say it's "crazy difficult" to set up, but it is definitely a little involved. There will be a ton of documentation on setting it up for an ender printer so that shouldn't be an issue, but it's more work than simply "install it and go".
The way your current set up works, is your pi/ octoprint is sending a file to your printers motherboard, the printers motherboard is processing the file and executing all of the commands. The pi isn't doing any real work besides letting you interact with the printer's motherboard.
In simple terms, the way Klipper works is by replacing the firmware on your printers board with a program that can talk to both Linux and the hardware of your printer (stepper motors, heat cartridges, fans, etc), using the pi to run all of the processing and such, then passing those commands to the printer's board (which is now essentially a zombie that does nothing but what Klipper tells it to do).
Doing the main computation on a strong computer like a pi rather than the weaker CPU on a printer motherboard opens a plethora of options, one of the most popular being something called "input shaping" which is very relevant to your question. What that does is tests the vibration resonance of your printer and modifies stepper commands to counteract them, allowing you to print at significantly higher (read: sometimes 3x or more than stock) speeds without much if any noticeable decrease in quality.
Not only stuff like this, but there are innumerable QOL improvements over Marlin. Object exclusion for when one part out of a multi-part print fails, custom macros for anything you could want your printer to do, graphic bed level mesh.. I honestly don't know how I used my printer for so long without all of these things that seem like no brainers.
Long story short, it'll probably take more than an hour or two to get set up, but as soon as you get it going you'll be wondering why you didn't do it day 1. If you're at all serious about getting the most potential out of your printer, it's an inevitability; the stock firmware is far too limiting in what you can do, and makes any kind of advanced tuning or tinkering either impossible or way harder than it needs to be.
Sorry to dump this wall of text on you! If you decide to give it a go, pick a weekend and hit the forums, shoot me a message if you get stuck on anything and I'll help you best I can!