• Payment Decorrelation
• Symmetric CSV Delay
• Signature Aggregation
• Splice-in/-out / Reanchoring
• Multi-currency support / Atomic Swaps
• Dual funded channels
• Combining HTLC Transactions
• Combining other transactions
• Spontaneous Payments
• Passing a transfer secret in the onion
• Invoicing Key
• Outsourcing Watching
• Backup and Recovery
• Using Multiple hops_data Cells in the Onion
• Streaming Payments
• Refunds
• Fast Failure
• Open Questions