The prices are set by the user. $1/gb is probably on the expensive side in Europe but nearly normal in USA and Asia. The price setting will have a helper tool to deal with various kinds of metering and billing schemes.

Yes, I just recently came up with a scheme that also, probably not coincidentally, uses timelocked BTC. It specifically requires a continuously active chain of time locked transactions that refer to the address of an initial TXID that is part of a node's pseudonymous identity.

Both age and size contribute factors in the random selection for peers to recommend relays (it has to be done carefully so as to not deanonymise recent connections). Age matters more, second is number of recommendations and third, and least, is the average amount of BTC locked on the TXID over its lifespan.

I'm glad to hear that my idea isn't entirely unique. It should ensure that it isn't profitable to spawn a node and then take it down, since one has to make a BTC tx as well as the amount, to prove arrival as well as to encourage a competition to have the highest lifetime average locked up. Nodes also contribute to this consensus ranking of peers in that they can raise the profile of reliable new nodes, but the primacy of the influence of age enforces maintaining a running, delivering node for a substantial amount of time before it even gets to get many clients connecting.

Ah yes, the last piece is that the benefit of locking up more is a progressively longer cycle for renewal. So, a sybil attacker is in a dilemma where they can lock up more, to get ahead of the new nodes, but then be stuck unable to spend that coin until a lot later, or use a smaller one and be at the bottom of the priority list for clients to select for first time usage.