Because FZ is the only EDA with breadboard view it’s hard to get parts, ie, low uptake low demand. Other problems is that hard to make modules in FZ even if you know how, because it takes a lot of drawing, and new ones appear every day so it’s hard to keep up.
Also all made parts are not stored in FZ so you have to do a Goo search to see if someone has made them. I usually search part names and add Fritzing.
I’m similar to you but a Mech Eng with only 2 years in electronics, so I’m no expert, but I think there are micros with builtin WiFi that use the Arduino IDE that would save space. Maybe Wemos 8285, but I don’t know because there are too many and types and I don’t follow any other micros other than the Mega2560.
I watch Andreas Spiess, but I don’t know if any of his stuff will help because I don’t understand most of it.
He has a Sonoff SC hack series and with a design of a made motherborad with modules attached, which should be like yours.