There’s not specific tools or interfaces for doing it, I was just doing something intentionally bandwidth intensive be measuring the peak throughout.

That’s right, there’s no real difference in the concept.

That's not completely correct, the BitTorrent DHT still has seed nodes same as everything else. You can't bootstrap peer discovery in a network with absolutely no knowledge of its participants.

P2PK was used with P2IP, meaning nobody had to interact with raw public keys. An exception is block rewards, which remained P2PK long after that went out of fashion.

In the original Bitcoin, you sent money by putting an IP address in the "to" field, your node connected to that IP address directly and requested a public key, and then you paid to that public key. Addresses were originally "offline addresses" for when the person wasn't running a node at the time, or for some other reason it wasn't possible to use this method.

This really has absolutely nothing to do with any differences in modern bitcoin, it’s just how it has always been. That’s a pay2ip transaction and they weren’t P2PKH “offline addresses” in the nomenclature of the time.

wallet.dat is not an Electrum wallet, it is a Bitcoin Core wallet.

Hashing the whole UTXO for Bitcoin takes many minutes, we expect the network to be able to synchronize in less than a second.

It’s off topic here, but your understanding of the basics here is pretty lacking, I’d do a lot more research on the fundamentals before trying to design something better. You would be absolutely nuts to store monetary values as a float for example.

It’s just not supported on modern nodes, it serves little to no purpose for anything other than abuse.