What is the point of trying so hard to save money when you already have an idea that it’s not ‘a good thing’. And, by your own admission, no experience to inform why this shortcut would slow you down with hours of debugging that can’t be easily solved. Ironically, once you really do know LoRaWAN, you’d then know enough to get a SCPF working with your devices.
And, in all your reading, did you not see the comments on the forum regarding SCPF’s? And if you did, how did you think your gameplay was going to be received by the community?
But fundamentally, why come up with a gameplan when you haven’t done anything practical yet and post it here - why not do the most obvious thing and just ask for advice on the best gameplay? And what the best learning resources might be.
So moving on from reviewing your gameplan, this may help:
Read: https://www.thethingsnetwork.org/docs/lorawan/
And this: Australian Student looking to experiment with budget lora tech - #15 by descartes
Good starter gateways are a TTIG or a Dragino LPS8 or LIG16.