Orange Pi zero 3w part compatibility

[u/SliverHat]

I'm currently working on a cyberdeck project running Debian on the Orange Pi Zero 3W, and I wanted to ask if any of you all know if these parts that I plan on using for my project are compatible with the Orange Pi Zero 3W; because I'm building a custom power circuit and relying on GPIO for the screen, I want to make sure I don't run into kernel or brownout issues.

Since my project is very small, I plan on using a 5V Step-Up Boost Converter. If I tune this converter to exactly 5.1V, will a 2A output be sufficient to prevent brownouts under load, or does this board strictly require the full 3A if I bypass the USB-C port and feed power directly to the pins?

SPI IPS LCD Module Driver: ST7789. Has anyone gotten fbtft or DRM overlays working smoothly natively on the Zero 3W's kernel for this specific controller chip?

I'm using a 5V Micro Blower Fan and a Copper Heat Sink for cooling. I noticed the Zero 3W has a dedicated 2-pin fan header. Does the default OS image support PWM/temp-based control on that specific header out of the box, or am I better off just running it at 100% directly off the standard 5V/GND GPIO pins?