Working on the bottom side I only used the heat gun really carefully on the resistors then used a soldering iron with a fine tip for the usb-c connector since the leads are fairly large.

Definitely would be more functional with more of the GPIOs exposed.

If you want an ESP32 dev board with GPIOs exposed there are dozens (or hundreds, maybe thousands) of other options out there. It makes sense not to expose them when you're going for the smallest possible footprint.

I don't know, I see enough space for four GPIOs there. Not holes, obviously, but pads should be very workable.

It could be even smaller without that USB C port and have more GPIO pads.

Thanks for checking it out!

Thank you! I agree, antenna definitely needs some improvement.

You should take the metal of the USB connector into account. This will significantly alter the emission pattern of the antenna. Try to find a radio amateur in your area, we have equipment to measure and software to predict antennas.