Do Bitcoin and LN nodes running over tor both use tor hidden services only? I'm not sure about the specifics on the comms protocol layer, I just figured they used exit nodes.
Follow-up question: which types of TOR nodes are involved in the end-to-end .onion traffic between, say, Tor browser and a server hosting the .onion service?
The browser runs a local proxy. The proxy sends a request through 3 hops (relays) before reaching the server running a .onion hidden service. The server's response goes backwards through those same 3 relays back to your browser.
Look into I2P, it's currently the #2 anonymity network and growing fast thanks to Tor reliability issues. In I2P, you must operate a relay/router in order to access the network. So it's more robust against DDoS since thousands of users aren't sharing a single relay.
You configure any browser to use your I2P router as a proxy (I2P daemon hosted on a separate computer ideally, or could run locally).
Requests are routed through 3 other routers before reaching the server hosting the .I2P site (eepSite). Then the server's response is sent back using 3 DIFFERENT routers. So, theoretically it's twice as secure as Tor since double the routing nodes would need to be compromised to de-anonymize a session. In practice, I2P probably isn't as anonymous because it has far fewer users and thus a smaller anonymity set. But this is starting to change. I2P also doesn't even support exit nodes, everything is a hidden service by default. There are ways to browse clearweb over I2P but it's more complex to set up yourself.
If you want to run an exit node you should seriously consider doing it through a company (you own or are employed at) or create a club/association/foundation.
I would recommend a VPS signed up with a nym and paid in bitcoin rather than using an ISP that is tied to your identity. Preferably one that is ok with running exit nodes
I think you're right. The sense I got was that it's not up to the hosting provider. Linode were actually totally cool with me running one (I reached out to them ahead of time), however they got served a notice by some automated intrustion report system and just forwarded it to me. It was all very above board, but it still sucks that they made me shut it down since ISP data collection is at an all time high.