Hi Jamie,
I was hoping to get a different answer, because that would be beyond my abilities…
I believe linuxcnc can handle a lot of these advanced gcodes. But honestly, even if you don’t know python, learning might be less work than setting up Linuxcnc. Python is capable of professional output, but is pretty beginner friendly. The interface to Marlin via gcode is pretty simple. Then you could start with something simple and grow it easily into a gui that could do what you want. If you wanted to outsource that, you can’t throw a rock without hitting someone that knows python.
I would just use a plain raspberry pi with the full desktop installed and either raspberry os or noobs. That will run a python script to send gcode just fine.
I would start with something simple, like just opening the serial port and sending a G1 command, and then waiting for the user to press ‘enter’ on the keyboard. Then you can add some simple input, like an old school game. ‘n(enter)’ for next row, (number)enter for more actions, ‘q(enter)’ to quit. Something like that would be a fun thing to write up.
After you have that ‘minimum viable product’, you could add (or pay someone to add) either a simple web interface (using flask), or a tkinter gui front end that would take the place of a keyboard. After that, you could just configure the pi to always start up to the program or the web page and hook up a 7"-10" touch screen and hand it over to someone else who can use it.
There are a bazillion tutorials teaching people to do simple programs like this with a raspberry pi. I would be willing to review it for you (but I don’t want to test it). Places like the adafruit, sparkfun, make, or raspberry pi tutorials would be great, because they target beginners.
Make sure you back up your work along the way. The pi sd card is not where you store information you aren’t willing to lose.
Looks like Marlin is working on some of these features now: