Fantastic news. Thanks man!
Ok, made some changes and put on github.
Seeking feedback, such as on the debounce circuit!
Nice board. Some comments. I always use surface mount parts. I found that they actually saved me time in assembly over through hole once you are set up, and are quite easy even for hand assembly. There are a lot of good tutorials online for a skillet / hot plate or toaster oven SM assembly. Or with this few components simple hand soldering. I’d use 0805 footprint parts for something like this.
The resistor and capacitor values are fine, but we went to a higher current circuit for the RC pair on the v9 (2.7K / 0.47uF). Either will work.
I’d put a silkscreen on every hole designating what it is. It’s free, and invaluable during debugging.
I’d add a test point for ground so you can solder in a dedicated pin and always have something to connect a scope or logic analyzer to.
A couple more observations - you might want a reset button on the shield as the shield covers the one on the board…
I think CoolantOn is an output, so it does not need the protection circuit. No harm if it’s there, though, other than the pullup will assert coolant on if the MCU pins go into tristate (like possibly during bootup).
@Alden_Hart Any idea when do you plan the major push to the edge? Thx 
If you tell me what branch you’re planning to push I’m happy to do a build and run a job through it if it helps. Can also confirm the fixes for probing and limit switch behaviors on the v9.
Latest board design is up at https://github.com/makerhqsac/tinyg_g2_breakout
I decided to keep with through hole parts even though I personally prefer smd parts. I have a reflow toaster oven and everything! But the target audience is people coming from x-carve/shapeoko builds who are looking to move to the next level, so I think keeping smd soldering out of the picture will make that smoother.
I have a set on order and will let everyone know when its proven functional. If you want to take a risk and get one before its tested, feel free! The link is https://oshpark.com/shared_projects/nkasJiEP