Parts arrived from Adafruit today! Pictured is all the main components, plus a gyroscope that I accidentally included in the snapshot. After checking the pins on the RTC, it looks like it takes 5V. Well, that won't work well with the 3.3V trinket and 3.7V battery. After some research, it looks like it can work with 3.3V logic by not soldering in the two pullup resistors. Easy enough. And for the voltage input? Let's hope that when Adafruit writes that it "works best" at 5V, it actually works at all at 3.3V. Hopefully I can test the OLED tonight with an Uno, and possibly poke around with setting the RTC.