At present, I’m working on an RC plane project where communication is handled via the NRF24L01 module. Thus far, I have thought to utilize an Arduino Nano, however I find it a bit oversized for the limited space in my build. I need some alternatives that are smaller in size and are able to function seamlessly with the NRF24L01.
Is there anyone who has used this form of compact microcontroller for such a purpose? Or are there any other microcontrollers or chips that you would suggest?
Dimensions are usually helpful in these sort of discussions 
Looks like the ESP12F is around 24mm x 16mm.
This is probably not what you are after, but...
Clem did a good video on designing your own PCB a while back but it was with a larger ESP32 module:
/challenges-projects/element14-presents/w/documents/5219/episode-485-bonus-content-how-to-make-a-custom-pcb-from-design-to-assembly---full-video
He also did a walkthrough video of a board with a couple of bare ATmega328 μC on it:
/challenges-projects/element14-presents/project-videos/w/documents/28271/handheld-basic-computer-in-badge-format-with-the-arduino-uno----episode-612
which could be handy if you have an odd-shaped 'avionics bay' to squeeze stuff into.
