A new protocol for Bitcoin has emerged: spark
It adopts an off-chain expansion method (similar to Ark, if you're not familiar, you can research it yourself). I believe this approach is a very good path, as it focuses on payments, is straightforward, and aligns with my understanding of the long-term development scenarios for BTC expansion. The content of its declaration is quite consistent with many of my viewpoints, giving a sense of encountering a kindred spirit. The protocol has a strong background, substantial funding, and is closely monitored by many BTC OGs and Tether, among others. The documentation is extremely organized and comprehensive, looking very professional.
https://docs.spark.money/issuing/introduction