Hi, great to hear you like TinyZero as an upgrade to TinyDuino! One of the major differences in use is the SerialUSB virtual serial port and the fact that opening the serial monitor does not reset the processor like with TinyDuino. However, now you can test if the virtual serial port is open or not, so you can put something like this before any SerialUSB output in your setup:
while (!SerialUSB && millis() < 5000); //On TinyScreen+/TinyZero, this will wait until the Serial Monitor is opened or until 5 seconds has passed
Then you will get all output messages after that. We've updated some of our examples, but it's still a work in progress.
Thanks,
Ben