Routed wires more neatly.
Decided to forgo the entire USB-C nonsense and just stick with the built in micro-USB on the Pico. Printed a new housing top to accommodate the different connector location, but I should still update the PCB design in KiCAD to remove the USB-C and fix a few other issues like the trace gap width and the pad extensions for the castellated contacts on the Pico. Installed the entire system and attached 2 fans to my roof ducts. One fan attachment used some 3D-printed screw adapters, and the other just used magnets. I used wood-glue coated cardboard as a low-cost water-resistant barrier on the ducts, which worked pretty well. The overall system worked pretty well. It dropped my attic temperature from around 90F to around 83F in 2.5 hours. 
Fabricated the PCB with the usual process. For reference 1/2 tsp washing soda in 250mL water for the developing solution and 1 tsp sodium hydroxide in 250 mL for the stripping solution. Need to make the gaps between the PCB traces wider and put some insulator under the USB-C shield. See video. 
Made slight adjustment to copper traces on PCB design and printed a UV mask. Also made a slight update to the software to hopefully improve TCP connections. 
Updated housing model to have flanges to screw into the wall. Printed in translucent orange (best color) PCTG and found 4 perfectly sized screws in my jar. Updated the Pico web server code to show the server start timestamp, hide the historical data by default, and update to the final 30-minute delay in datapoint recording. 
Designed 02007-002 and -003 housing components. There are holes in the box for the antenna (unnecessary), USB-C connector, motor wires, and sensor wires. 
Designed circuit schematic and laid out PCB design for the control unit. 
Spent a while getting the connection to the time server working. Attached UI image shows a datapoint every second for testing purposes, but will probably be every ~30 minutes in the live version. 
Got the preliminary software mostly working. Ignore the broken UTC date, having some issues with the time server. It allows GPIO control of a Pi Pico 2W thru a webserver, and that will eventually toggle on some small vent fans. It also reports the temperature and humidity. I could eventually add logic that turns on the fan based on the relative temperatures inside versus outside. 