I wouldn't reset anything. Within a day or two your devices (especially powered ones) should all find their routes updating to the hub directly. The antenna thread discusses people's experiences.
As for the zwave "why can't it just?" questions, I would say that route finding via multiple hops on RF is not an easy problem to solve. Signal strength and interference vary constantly, so there is no good time to run a "analyze NOW" task to capture the state of the world as you might in a wired (comparatively interference free) environment.
I believe Insteon used a system where every node got the entire network "map" (so devices could talk directly vs having to use a central hub) plus they had powerline as a secondary transmission method. Zwave only captures "near" devices based on signal strength and tries its best to figure out the optimal route over time. Insteon also allowed each button controller to talk directly to any and all dimmers without going thru a hub. The rules and maps had to be duplicated everywhere but it did make communication quicker in cases like that. Zwave does have some options for device->device communication (using a concept called associations) that can help in some cases.
Personally I've not had anywhere near the issues with zwave devices as you've been sharing. I never repair my network, I've had maybe 1 device ever need power cycling after a storm, With no ghosts the 900mhz zwave network (especially of all zwave plus devices) has been rock solid for me on both ST and HE.
Also note, there are 2 types of zwave repair. An overall repair (run by "Repair Z-Wave" button at the top of Settings->Z-Wave Details) and device repair (run by the "repair" button on each device with a route.
The overall repair is documented here: Z-Wave Repair and here https://docs.hubitat.com/index.php?title=The_Anatomy_of_Z-Waveâ„¢_Repair
The device repair is mentioned in the docs as: " Repair will attempt a per-node repair (recommended over a full network Repair Z-Wave when possible)."
I personally have only run a full repair rarely and that was when adding several devices "mid mesh".
Would you share your current zwave device list again since you started over?
Also share your zwave topology map (Settings->Z-wave Details->Z-wave Topology).
I also think it would help to document the other failure cases you're seeing. As you mentioned in your mechanic troubleshooting analogy, lets go thru the failures or issues and see if we can find solutions. For instance, if you have a rule to turn on a bunch of switches on a motion sensor event, some people have found that once you reach 4 or more switches, they don't necessarily reliably all turn on. HE's "Groups and Scenes" have helped people with that, as have the zwave radio firmware upgrade. You may already be using those, but lets isolate the action reliability (turning on/off the group in my example) from the event reliability (motion sensing) for each of your failure/frustration cases.
