Bitcoin development is happening very slowly and I am not sure what is planned for the next soft fork. One thing I am looking forward to though, is the Eltoo upgrade for the Lightning network. Eltoo requires a soft fork for SIGHASH_ANYPREVOUT, so I guess that is what I am looking forward to the most.
Apart from that, I am hoping for more developer tooling for Taproot to make it easier to leverage all of its capabilities.