LOL... that sounds like a dream job for me; getting paid to tinker with 3D printers all day. *sigh*
Sometimes it is fun, sometimes it's a huge pile of frustration. My current job time is split between my new R&D work and my previous work on the production line. So I get to try and work on firmware and electronics. But I still spend more time basically being quality control and supervisor of the calibration department, where we spend too much time adjusting every printer manufactured to run optimally. It often gets frustrating when I'm fixing the same production mistakes over and over.
The other frustrating thing about it is that while I am running around helping keep things working I get all these big ideas of cool things we could design into new printer models, or new features we could put into the firmware, but we just don't have the time and people to work on all of these grand ideas. We do have some interesting things in the pipline though...
I also have this constant feeling that since I have access to all the 3D printing capacity I could want that I really should be thinking of things to print as much as possible.
And if Marlin is any indication of even the neighborhood of the state of the art, I'd be worried that your Kung-Fu is too fresh, not too old.
I think that the current 3D printer industry is based off hobby guys with their Arduino based boards is what made the whole thing possible to get going. It didn't take a huge amount of sofware development skills to get the first machines working. But at the same time I think it might be an anchor slowing the development down as well. Take what I was previously talking about as an example. I had a situation where I wanted to hook up an in circuit emulator to the controller, load up the code, and when it did something we were interested in, stop the code and step through it to see what was going on. But I don't think anyone in the whole history of Marlin has ever actually debugged the code with an emulator and debugger software. Yet I learned that stuff back in the mid 1990's at my first job out of college at an electric fork lift company. Back then the emulator was a big pod you had to plug into a socket in place of the processor and it cost $20000 instead of a $160 Atmel-ICE pod, and I worried every time I used it that I would somehow blow it up, but I could debug code better then than what I can do now. The whole Arduino community has never had the "luxury" of being able to debug code with advanced tools. The best debugging you could do was to litter serial print commands of stuff you want to monitor throughout your code. But there is a "release candidate" 2.0 version of the Arduino IDE available now that seems to be based on VSCode and has debugging capability included so maybe that is changing...
As for McBryce's 32-bit/Trinamic board... I'd guess his is one of the many that came with the drivers soldered in; I'm pretty sure he's savvy enuf to know the Trinamic drivers are platform-agnostic. That said... I imagine that if he wants to enable a bunch of features along with managing those drivers in the firmware, he may very well need the 32-bit processor to do it all. Especially if he's using a touchscreen panel.
mnem
I am just getting into the Marlin stuff so I don't know if there are features in the mainline Marlin code that we aren't using at Lulzbot, that if enabled would be too much for the 8-bit boards. Could be, but one interesting thing is that a lot of the touchscreen panels, including the ones we use at Lulzbot, have a secondary processor right on the LCD. So the main board running Marlin isn't pushing pixels directly to the LCD constantly. Instead it sends higher level GUI commands to the LCD to draw buttons and display text and stuff, and the chip on the LCD handles that, and sends back coordinates of touches on the screen. So having the high res touch screen probably doesn't add much overhead over the older style "glcd" that most printers use, including the non-touchscreen Lulzbot models. We even use a touchscreen on the Lulzbot Bio printer that runs the same 8-bit controller as the Lulzbot Mini 2 and Sidekick printers.
As opposed to tinkering on printer-printers all day... which I've done, and is a complete shithole deadend job...
I've had a couple times when I told people I work at a 3D printer company, they say something like "so you can fix my laser printer then?" and I had to explain the difference. I didn't admit that I could still possibly fix their laser printer even though they have little to do with 3D printers.