Okay, I forgot to mention a few things in my last update:

I've added a second battery holder. I was going to just use two CR-2016s in the one holder to get up to at least 5v, but I want more time per pair of batteries.

I've added a count up/down limit timer when the device is tilted or not to make sure it doesn't reset when the table gets bumped. Also I have a dim light when it's counting but before the green light as well as a purple light when it's in tilt-reset mode.