Most Odroid boards have arm processors, but the H3+ has an Intel N6005.
The communities on different instances are not the same. You can subscribe to both. The idea behind federation is that one company/server can't control all the traffic. It might result in a little splintering of communities, but I think it's ultimately better to be decentralized.
All the cards in this stack below the 4080 need to be shifted down a tier. The pricing on this entire generation is insane.
That is one that I haven't done yet, but I've found this guide to be a good outline.
It's still in the works, but I'm planning on:
It's definitely a lot of stuff, but I'm trying to reduce my reliance on cloud services. Really excited to get this stuff going.
The Belkin RT3200 is a pretty popular router for openwrt. It's a Wifi 6 router and you can usually find them cheap on ebay.