And if you go offline for a few hours, your peers can steal your balance (unless you entrust somebody else to monitor it for you, which has its own tradeoffs)
I think a combination of both is required for optimal results. Lightning is good enough for micropayments.
On chain transactions are good for large payments. The only problem with on-chain scaling is that keeping a payment history for the entire planet is not really feasable. You have to somehow prune old data from the blockchain.
I'm sorry, but I'm not impressed. Let's build a solution that scales better on-chain and uses a more power efficient mining algorithm.