Ethercat LinuxCNC board for a 4 axis router

Lately I started looking with great curiosity into LinuxCNC, because it seems to be one of the nicest and most affordable options to get EtherCAT and recently even s-curve acceleration control! In other words, as far as I know, it's the only solution on the market that offers such badass features as well as full configurability at a fraction of the price of other devices.
My current experience is with Mach 3 and UCCNC, but in both cases I was dissatisfied with motion planning where the machine would stutter a lot with complex toolpaths or with larger error allowance, it would run smoothly but it would mess with the surface finish.

My biggest hurdle right now is finding the right hardware. I saw countless solutions and configurations to get this done and I'm looking for something well proven that's not too hard to set up and doesn't look like spaghetti.
I was looking into Mesa boards, but even that got me a bit confused and I don't know what I should get. What's important for me is that the board offers screw terminals for interfacing with endstops and VFD and ideally it has its own computer - i.e. Raspberry Pi.
Could I ask someone for some recommendations? 

With EtherCAT you typically do not use a motion control card (Mesa, Remora, etc)
but rather use EtherCAT capable motor drives.

Yes, I understand that, but I still need some hardware that can do the following:
1. Interface with other peripherals such as relays, emergency stop button, endstops (unless I use sensorless homing), VFD
2. Have ethernet
3. Host a raspberry pi
4. Ideally offer photocouplers for some inputs

So I guess at the very least, I'd need some kind of a breakout board for Raspberry Pi that is known to also work with Linux CNC. Does it make sense? I'm really lost in this whole topic. Ideally it would be something proven that people have already tested in a similar configuration that I require. I just know that if you have something like Sinumerik controller or even Acorn Hicory, it's kinda what I wrote above, minus the Raspberry Pi and I thought I will need something similar to run LinuxCNC on and have the IO exposed.

I just realized there are also EtherCAT IO interfaces, so if that's supported, I could indeed get away with basically "ethercatting" everything without any extra "controller board"? That'd be incredible :O does it actually work with stuff like this too? www.aliexpress.com/item/1005006811064267.html

Depending on the drives, you might have enough I/O from the built in digital I/O on the drives themselves

Yes, there are generic Ethercat IO modules but many of them will require you to write a driver for them.
An alternative is to look at a Beckhoff EK1100 and add modules to it to unit your needs

 

These can be pretty expensive but man of them are supported in the Ethercat hal driver.
You can find them second hand reasonably priced on ebay