Good explainer. One thing people miss: "send back and forth instantly" hides a lot of complexity. Each payment needs a route with enough capacity on every hop, and if one channel in the path is depleted, the payment fails. That's why you see people talking about inbound capacity, submarine swaps, and LNDhub — the UX is simple, the plumbing is not.
The "final balance hits the blockchain" part is also worth expanding: you don't settle every time, you can keep going for months. The on-chain transaction only happens when you close the channel. That's where the real savings come from — one tx instead of thousands.
